Quick Random Note:
Here is the list of characters that cannot crouch Guile’s Backfist (Toward+Fierce)
Sagat
Geese
Raiden
Zangief
Chang
I thought it would be interesting to mention that because there are many tall characters but only a few cannot crouch his deadly punch. For instance the giant rugal can crouch it.
I find this move better than Roundhouse Kick, because it comes out faster, is better anti jump move, and is harder to punish.
I won’t say abuse it against these characters, but mix it up (c.mk, and HK come in mind), and use it more as whiff punisher and in your block strings. Fighting Geese and sagat becomes much easier. Anti airs sagat jumping over SBoom perfectly (beware of low jump over SB as always)
My only regret is that it whiffs on Blanka Ahaha!
Hope this stuff helps a bit^^