I have posted a thread about this before not long ago, surprised not many were interested although I was rather bothered about this. I really thought it will garner at least some attention and discussion, but it was barely 1 page. (Not that I'm attention seeking!)
By disabling 'Increase Contrast' in Accessibility under Settings, it lags your phone to an extent. Animations are not as fluid as when you enable the setting. When you enable it, u pretty much lose all the transparencies and eye candy, but u will gain a noticeable improvement in terms of general smoothness.
Here's my
thread