Thunderous Blast - I'm not loving it.. I must be doing it wrong

I have a Dark Electric build I am working on and have Thunderous Blast. Here are my issues.

If I am in a team, Twilight Grasp and my other debuffs seem more important to keep maintained then dropping a TB shot, which is not killing anything atm slotted with SO's. I noticed of course when I use TB in a group everything goes down the crapper. Twilight Grasp cannot be used when needed, which includes myself. Shadowfall really did make a difference.

If I am solo I am running 0 +5 and again using TB anytime ends up killing me or almost killing me as I use a bunch of Insp to get me back up and running after using TB.

Is the power just that situational or am I just doing it wrong. I am feeling I could use something more useful in its place. I was thinking it was going to be more like a Blasters nuke, which it seems it is not.

Blaster nukes can start and finish a fight in one go, with the higher base damage and Aim and Build Up. Defenders cant, even with a -Res boost to your damage like Tar Patch. You're probably best using it to end a fight rather than to start one.

I'm not a big fan of nukes on my Defenders, especially if, like you say, you have to drop an important toggle like Darkest Night to use them. Even on my Kinetics Defender (no toggles and nice big damage boost) I never used it that much.

When I have taken them they're situational. If I've aggroed two groups and the fights going badly, and a lot of the enemy are at helf health, I'll maybe nuke.

In general the best Defender Nukes are the ones that deal damage but also prevent the suviving enemies from attacking. Physchic Wail and Atomic Blast both mez any suviving minins and LTs giving you a bit of breathing room. Blackstar floors their to hit chance which is almost as good (and works on bosses). In theory Thunderous Blast can be used for a similar effect (no endurance and no recovery) but it can't do it on it's own, thye need their endurance drained before you set it off.

Slot some endmod into it, it still won't kill them but if my blaster can turn TB into a full drain attack by itself a defender should be able to as well. Bonus points: TB hits them with a recovery debuff as long as the one it hits you with, so it's effectively a mez when it bottoms out their blue bars. And since it's not magnitude based, works on bosses (but not AVs.) Admittedly most enemies get back into the fight quickly once the debuff wears off (assuming you know, survival) but it still takes a couple ticks of end before they can ramp up to their big hitters again.

[edit] added boss comment