I don't think it's even possible like that. That is, if I understand this correctly.
Just to make it clear, you mean that in one exchange, the stress track would have to go from something like this:
OOOO (OO)
to something like this:
XXXX (XX)
or they get to completely clear their stress?
That's going to be really hard to do, because that's going completely against how the mechanics around stress work. A big problem with this is that the target can only take 1 stress box for any attack. Which means you need at least a number of attacks per exchange and therefore characters in the scene as the stress track is long. If you go with a hulking size, mythic toughness monster, you'll quickly see how absurd this can get. Also, hitting the 1 shift stress box can be quite complicated, if you are running around with a weapon.
Keep in mind that you can still kill a character with toughness, it's just, well, tougher to do, because they soak part of the stress they take with the armor the power provides.
If you want to go recovery, go recovery. The power is already there, and it works well. Is there any particular reason you'd need a power exactly like this? What exactly are you trying to do?