The defense bonus that stealth and invisibility gives vary by archetypes. 1.75% looks like blaster numbers. Stealth actually gives 1.75% defense to all that is unresistable, and 1.75% defense to all that gets suppressed when you attack/are attacked. So as a blaster, you will get 3.5% defense to all when in stealth, but if you attack or get attacked it will drop down to 1.75% (unenhanced) Also your stealth radius gets suppressed to 0 if you attack or get attacked with Stealth running.
For Invisibility, you are correct, you can't use any attacks and the defense bonus doesn't suppress when you're attacked, neither does your stealth radius.
Someone with the numbers will have to answer the first.
Invisibility (and Phase Shift) are toggles.
You can't attack while using Invisibility.
If someone else hits you with Grant Invisibility, they're invisible until they attack.
Phase Shift works for 30 seconds at a time.
If you want Invisibility without the "no attack," at 20 you can go into Siren's Call. You can (by doing the patrol) be awarded a "Combat Invisibility" which WILL let you attack. You can be awarded it three times, each one lasts up to 30 minutes of use. (I tend to recommend the Warburg temp power over picking up Phase Shift as well.)
The -speed penalty in Stealth is a real drag.
If you do anything that is regarded as an attack, even if non-aggro like casting Smoke or tossing a Smoke Grenade, you'll be subjected to 10 secs of stealth suppression.
Teams are the number one killer of soloists.
I have never ever picked this pool so I had a few questions.
So stealth gives a 1.75% def to all but when you attack you lose some of that bonus. How much do you lose?
Invisibility gives a 7% def to all but you cant attack? Its a toggle like PFF?