Lag tactics is for SCIV the only semi-lag tactic is Ivy's 1k and that isn't really a real lag tactic in SCIV, even if you react you cannot block the low only before you guard before the low attack will your crouch blocking guard connect, but with Ivy if you react fast enough you can block it so there is really no lag tactics in SCV, which I noticed this when the game came out on the first day.
However if we are talking about lag i see plenty of it and people abuse it and even say 2 bars is fine which is obviously not, and the funny thing is i get a delay and the other guy does not, its obviously done on purpose to their advantage this what we usually call a "lagger"