Because i want everything to be controllable and changeable anytime and very FAST. It is not about my laziness, I am composing for commertials and customers allways want revisions "ASAP" :). I hate record everything again and there is no time for V-vocal, bounce etc. lots of audio file. I dont think that time and pitch change at the same time will be problematic. There are other DAWs already doing that without problem. Anyway, it would be time (and money : ) ) saver for me.