QUOTE(purple dolphin @ Feb 11 2007, 11:49 PM)

I wouldn't say you were doing too much, but I would definitely not try to put an aim on how quickly you do your grade 8, because that will add unnecessary pressure, and I don't think anyone should start an instrument just thinking, "I want to do grade eight in X years". Keep it as a hobby if you do take it up, and don't put undue pressure on it, as really IMO, your maths degree and your piano should come first.
I would take it up, see how it goes and then go from there, but just play for the sake of playing, and not for the sake of, "I want to be this good in this time".

^ wise advice IMO

I was trying to think how to reply, but I think PD said all that I'd've said and much more clearly than I'd've managed!
Suck it and see - don't put undue pressure on yourself - see how it goes. Time will tell how fast you progress, by all means practice and ensure you have the best technique you can manage (good technique and playing easy pieces will set you up far better than rushing on and not getting technique right - as one who hit the brick wall on the violin, trust me on this one

) but just see how it pans out and enjoy it