When I first saw this thread I thought it was a joke made by someone with internet problems, reading more I begin to understand that you actually put a 400ms delay on spells. What the hell?
This is a game, we play it to have fun and lag only makes you frustrated. You think that anyone, after carefully paying attention to their position, skillfully avoiding a CC and then getting it anyway due to this delay, will take a step back and think "This reminds me of the good old days, I'm having so much fun"?
Keep in mind that many mechanics from the begging of wow were based on the fact that internet was bad. If you wanna replicate blizzlike TBC experience, why don't you also disconnect people randomly, simulating internet connections of 2007