I wouldn't do it. I mean as another member told you some pro's do it but I believe that's to plink maybe, you shouldn't do it every single time, why would you?
huh? plinking and double tapping are different.. theres double tapping hitting the button 2 times fast with 1 finger / drumming 2 inputs with 2 fingers almost like plinking except on the same button with the button having to neutral inbetween so like a fast gallop with index ; middle finger preferably.
plinking is entirely different.. plinking stands for priority linking and its not needed in sfv due to links being 100 frames (jk) but really.
how you plink is say you want a 1 frame crMP link or w/e such as eryu axe kick bnb in usf4. you tap medium punch and light punch almost at the same time (with medium being ever so slightly before) basically hitting 2 buttons but 1 finger would be on a slightly lower pivet rather then hittin 2 buttons exactly the same time. You used to be able to plink a lp meaty with stand tech (throw) for OS if you mistimed the meaty, but they took it out a while ago along with some other OS's
also you can do like a quad type input plink for ex; sakura heavypunch L tatsu loops by plinking HPMPLP
so the input would look like this on your screen
HP
HPMP
LP
Then of course there's like piano'n etc etc for chun legs in usf4 and some other things, but you don't really need to learn any of these in sfv. double tapping isnt too bad of a habbit. i know for sure daigo has always drummed every input (even fireballs lol)