I believe you can plink special moves with button combinations like HP+HK (disable taunt), MK+HP, LP+MK, and LK+MP (among others like LP+HK, etc.). Can you plink LP+LK for specials? I dunno.
I know I should probably be plinking things such as Adon’s Instant Air Jaguar Kick, but I don’t… as the hand positioning is extremely awkward for me and introduces a lot of tension in my hand.
Special moves have buffers (like 3D games have buffers), so most of the time you don’t need to be too precise, e.g. mashing out a 3f Shoryu block punish. Or even Ryu’s SPS, HP SRK- not hard at all to link because of the buffer period.
As mentioned, plinking ultras isn’t really utilitarian. Very specialized… like, you can plink into a standing 720 . . . but who does that?