After my sheik got bodied at xanadu I decided to vent my frustrations in the lab for DHD.
A little more optimistic about him now, while dthrow > fair itself doesn't kill, depending on % and Sweet/Sourpot, it does frame trap for frisbee which true combos into kill moves, and is the best option to punish di away + jump/no air dodge. Faster fallers actually have to tech at times to avoid it. Often times, characters will be too low too air dodge properly, and they can only jump towards if they want to jump away since away/straight up will get them hit by the frisbee. Against most of the cast, this is an almost guaranteed upair if reacted to properly.
If it sends them offstage, it's a similar situation if frisbee connects it true combos into fair which while that close to the blastzone can certainly kill reliably early. Otherwise, they have to jump again in towards dhd. He actually doesn't gimp too well, the angles his moves put people at just don't allow it and his spike is very weak. So this mostly just sets up for a kill opportunity.
Furthermore, my findings with fair prove American DHDs really have been playing this character wrong. Just standard pokes with it accomplish this frame trap, but the move itself frame traps for grabs at certain percents, and sourspot combos into itself, start tech chases, so just one fair connecting is pretty significant.
(Personally I thought most always played him wrong, trying to camp with slow, combo starting projectiles but never being there to follow up? And you wonder why you don't kill?)
There's also a lot of untapped potential in the reverse shot game. I don't want to sound conceited but I think I'm the only one that really knows how to use it.
Self-plug
It's a frame trap in the truest form. When coming back, you can't air dodge it, you can't jump into the stage or ledge for safety... It's really easy and potent offstage pressure imo. Almost guaranteed against a lot of characters. Similar to Ness's pkthunder pressure though much more technical.
Some Concerns Though:
Diddy, Ness, and Sonic remain about the same awful MU wise.
For some reason, diddy's hurtbox just after a landing airdodge is lowered, disallowing dhd to punish it with frisbee. (Wtffff)
Ness's air dodge and options out of it means when we read the air dodge, it's still a 50/50 on whether we get the punish cause we need to read the direction too. Due to the endlag on frisbee, ness can convert a kill off this himself if we guess wrong or even space wrong. You also need to commit HARD to punish ness's air dodge. Like, perfectly timed between short and full hopped and going deep as hell.
Since this MU is so dependent on negating rage ness as much as possible, I don't think this is a huge boon.
And sonic has the dash speed to consistently punish frisbees on shield from like almost the entire range of the move with dash grab, then set up an edgeguard opportunity. Spring lets him opt out of the option select, and there's absolutely no way dhd will kill a spring landing sonic.