Personally, I feel it's almost impossible to truely learn much about push hands, let alone Tai Chi, any way but face to face.
I completely agree with you on that 5AnimalTom: books or videos are no substitute for a credible instructor and for classmates with dedication and consistency in their practice. If used, they should only be viewed as supplements to personal instruction. But are you saying that you wouldn't or don't find even observing video of others practicing the form or push hands valuable as a learning aid at all?
I'm not sure I agree with that; observing others has always been an important aspect of learning--granted we should not resort to watching videos when a fully capable instructor is available within reach, but if one is unable to observe a master in person why not watch him or her on film? If nothing else it can inspire you to work towards such a level of skill.
What are people's thoughts on this question?
It may be the case that watching others perform push hands requires a more careful eye given it is not regimented and organized like the form but an interaction with another person, but I still believe observing real masters can provide useful insights and inspiration--even if it's only film.
Respect the Art and respect the Teacher and you will naturally receive the true transmission.
--Y'ang Ch'eng Fu