Like I said earlier, lag depends on server output, computer specs, the amount of people in that area etc. You are putting more stress on the game by being able to move quickly through combos, but it will not be significant. A friend of mine experienced the same thing, and I suggested to turn the display settings down a notch. Low and behold, he can fast switch at his full potential without witnessing any lag-like symptoms. Keep in mind though, this was a mistake made by POTCO. If TLOPO brings back this feature on purpose, I'm sure they would do it the right way, and not have it stress out the system in any way, shape, or form.