I only ask because I`ve increasingly noticed that many pieces that I play contain 10ths and even 12ths and I can only just reach a 9th, so I have to glissando each chord which can present technical difficuties such as trying to play melody notes differently to the others , trying to glissando downwards can be extremely awkward.

Rubinstein had fairly average hands (I think!), my teacher has smaller hands than me but he can still play rachmanninov without any fuss, its all about finding the right playing style for you`re hands, no one style is suitable for all hands. I could launch into a lecture about how to properly train your fingers, but its 1:00 in the morning, so I won`t

I`ve got the biggest foot!

Pretty dumb topic I must say.... I dunno- if it`s an eleventh or twelfth stretch, I doubt you`ll be able to make it. My hands can reach up to an eleventh- just barely though