Alright, a bunch of people have posted the problem I'm about to describe, but I figured I'd pitch in with an actual example of a character I have on live, and do the math through. So, first, a few points.
-This is a claws/SR scrapper
-I am NOT a min-maxer. Especially on this guy. Almost every power he has, I either threw one/two commons into, or a single full/mostly full set. He probably represents a somewhat typical IO-set-heavy, non-minmaxed build.
-I don't know the full AoE modification for PPMs offhand. That said, I do know how it works with ST attacks, and every attack I'm going to discuss is ST.
-While I may not have squeezed the hell out of this guy's build, it's not for lack of math skills. My degree is math-related, and I have taken a few courses in probability theory, so I have a general idea what I'm talking about.
-I don't know the game's underlying numbers by heart, and have pulled my data from Mids'. That said, all calculations of proc rates based on that data, are mine, and you could change pretty much every number I grabbed from there, and still see the same conclusion.
So, on to the scrapper. Claws/SR. With Hasten off, he sits at about 86.25% global recharge. Nearly every power he has takes LotG, and SR also has quiickness, so this wasn't terribly difficult.
Against single targets, his attack chain is one of the following:
Slash - Strike - Follow Up - Strike
Follow Up - Strike - Slash - Strike.
You'll notice that these are the same chain. Basically, I open based on whether an enemy is likely to dodge me (and thus Slash's def debuff will help make sure Follow Up lands), or is gonna be pretty easy to hit (start with the buffs from Follow Up). Now, the exact details of these three powers are mostly irrelevant, since this discussion is going to be about one thing, and one thing only: The procs.
Two of the above powers have procs. Strike and Follow Up each have a full set of Mako's Bite. This also means that they have the same accuracy, the same damage buff, etc., so I'm going to completely ignore those, and assume that every attack hits.
(As an aside, if someone wants to recheck my math, the last thing you may need to know is that Slash has a full Scrapper's Strike)
Also, my recharge isn't enough to have perma'd hasten. It ends up with about eight seconds every two minutes where it's off. I usually spend those eight seconds not attacking, making sure Practiced Brawler is up, etc. Since the below discussion will be about a very short loop, I'm pretty safe in ignoring this as well.
The gist of my argument is this:
Making PPM rates based on modified recharge values is a downright toxic decision. Any build including procs will suffer when given recharge boosts, because this will NOT increase the rate at which the powers fire, but will decrease the proc rates.
Alright, on to the numbers.
So, the first problem I have pops up right away. We've been told the PPM rates will increase, so I don't actually know what PPM rate is going to be. That said, it's actually mostly irrelevant. Nonetheless, let's analyze my current proc rates, and see what we come up with.
CURRENT VALUES:
One full cycle of my attack chain takes 5.28 seconds to execute. I queue up each power before the previous one executes, and I generally have a very low ping time to the server, so I am generally able to maintain that speed as long as I want.
The proc in Mako's Bite has a 20% chance to fire, and deals 71.75 damage at lvl 50.
So, in Follow Up, MB's proc has a chance to fire once every 5.28 seconds, with a 20% chance to fire. This averages out to 2.2727.... PPM. At 71.75 damage, this gives 2.71780303... DPS added to my attack chain by the proc.
In Strike, MB's proc has the same chance, and twice as many chances to fire. That gives a proc rate of 4.5454... PPM, and a DPS boost of 5.4356060... DPS.
So, the point of looking at my current values was to see what PPM I should expect from Mako's Bite. Strike fires off quite a lot, and only gets up to about four and a half procs per minute. So, just to allay anyone countering me with "But they said the PPMs will go up!", let's assume Mako's Bite gets a whopping 6PPM rate. It's absurdly high, and it's also nice and even (average of one proc every ten seconds), so it makes the maths easier on me.
New Proc, assuming 6PPM:
Assuming Mako's Bite is converted to a PPM-based proc, is given a whopping 6PPM rate, and all PPM-based procs are converted to use actual recharge, not base, I get the following numbers.
Follow Up now triggers the proc at a 45.5% chance.
This gives a rate of 5.1704545... PPM
This gives an added DPS of 5.4356060... DPS from the proc.
Strike now triggers the proc at a 21.6% chance.
This gives a rate of 4.9090... PPM
This gives an added DPS of 5.8704545... DPS
Already, I see a problem. My scrapper is triggering this new 6PPM proc less than six times per minute, per copy. Strike is actually firing at less than five! What gives? Well, I can't fire Strike as often as it recharges. In fact, it spends a lot of its time sitting in my tray, recharged, waiting for me to animate through Slash or Follow Up. Similarly, Follow Up recharges right around when I start the Strike before it, so it doesn't fire as often as it could.
This isn't my argument. This? This is acceptable, sort of. The fact is, the existing for of Mako's Bite also only fires, at maximum, as often as I cycle my powers. This, in and of itself, still isn't my issue. My issue is what happens next.
Let's say I get hit with Speed Boost. Kinetics is a fairly common set, I have a corruptor with it myself, and Speed Boost is generally considered a very solid buff. My scrapper doesn't really benefit from it much, but it certainly doesn't harm him, and if nothing else, it brings Hasten up to the point of being permanent. Currently, if I'm hit with Speed Boost, my Mako's Bite procs still fire once every five attacks, my attacks still animate in the same time, and I still have the same DPS. But what about these new procs?
New proc, 6 PPM, Speed Boost:
Same assumptions as last time, only now, we add 50% global recharge from somewhere (it actually doesn't have to be SB, I'm just offering that as a possibility)
Follow Up now triggers the proc at a 40.5% chance
This gives a rate of 4.6022727... PPM
This gives an added DPS of 5.50355113636... DPS
Strike now triggers the proc at a 20.3% chance
This gives a rate of 4.982727... PPM
This gives an added DPS of 5.5171401515...DPS
Whoa! I was hit by Speed Boost, and it made my main attacks weaker? Yup. Speed boost now has a hidden -DMG component on any proc powers. At this point, Strike is already recharging noticeably faster than its cast time. I could probably fire it non-stop. Nonetheless, I still slip Slash and Follow Up into my attack chain, since the buffs/debuffs are very nice. And look, neither of the powers I have that Mako's Bite proc in is actually able to trigger it at a rate of six times per minute.
Okay, this is interesting, but now let's try something else. My server has Rikti Ship Raids once a week, and at such a raid, it's not unheard of for me to get so many recharge buffs flying around that I sit at the recharge cap for much of the Raid. Let's try doing the math with that, shall we?
New proc, 6PPM, Recharge CAPPED!:
Follow Up now triggers the proc at a 32.3% chance
This gives a rate of 3.6704545... PPM
This gives an added DPS of 4.38925189393... DPS
Strike now triggers the proc at a 18.1% chance
This gives a rate of 4.113636... PPM
This gives an added DPS of 4.9192234848...DPS
Yeah. They both went down quite a lot. I've got a 6PPM proc in these powers, and it's firing about three and two third times a minute in one, and about four times a minute in the other.
I honestly do like the fact that all IO procs are moving to PPM-based procs. That's great, and I support it.
I don't particularly like that the cap is going to be 90%. But, while I oppose it, that's certainly a matter of opinion, and I'll accept it moving to 90%.
And, of course I like PPM rates being increased.
I CANNOT accept the fact that PPM rate will be based on modified recharge. If this happens, any character with a consistent attack chain will be unfairly penalized by outside buffs. Until now, recharge-boosting buffs could only help. If I didn't want the extra recharge, I didn't have to fire my powers any earlier. Now, every bit of recharge I get will make my procs less powerful, even if I can't fire that power any faster. Does this affect minmaxers more? Sure, they tend to have heaps and heaps of recharge. But lots of people participate in things like Zombie invasions, Rikti Ship Raids, Rikti Invasions, etc., and any of those things can easily attract enough people with recharge buffs to cap anyone's global recharge.
I do understand where the devs are coming from. A power with, say, a 20s base recharge, will get a 100% rate on a 3 PPM piece, even if it gets fired WAY more than once every 20s. But using the modified recharge goes too far in the other direction, especially since you actually have to be an incredibly good minmaxer to make sure you're firing every single power you have, exactly at the moment it recharges.
All this being said, I have to wonder if there's a balance somewhere in the middle. I'm not willing to go through the math over and over, but I have a few thoughts, and no idea if any of them would work.
Only use enhanced rech, ignore buffs.
Only use enhancements and set bonuses
Only use constant recharge bonuses (i.e. enhancements, sets, auto powers)
Only use recharge bonuses coming from self.
At the very least, I don't think that other players' recharge-boosting powers should somehow weaken my attacks, as it almost makes me want to shelve my /Time Mastermind and my /Kinetics corruptor.
(Oh, and if anyone spots any actual math errors, please feel free to let me know.)