I've become suspicious of instruction based on feeling, because how each of us interprets what he does can be quite different. Something that feels effortless today could be the result of a lot of effort based practice yesterday.
Well without getting metaphysical - its pretty likely that similiar muscle use feels the same between people. Loading the legs and hips feels similiar. The feeling of letting the racquet flow through (after the hip drive) rather then swinging it feels similiar etc etc.
I don't think we need to be suspicious of feeling at all. Its probably the main way players learn IMHO.
A very simplified view of the learning process is that we would watch other players - try to hit the ball something like they do - and then we get feedback from seeing how the ball reacts. When we hit good shots we remember how this FEELS and thus we try to replicate that feeling.
Video certainly is no pancea. I haven't seen any explosion in player ability with the advent of video. The problem is I would hazard a guess is that even if you can see how a person plays in slow motion you have limited abiity to replicate that because you don't know the muscle firing pattern to actually achieve that. Essentially you don't know the feeling..