Re: Poll: How effective is learning aikido through a purely visual media (videos, DVDs, software, etc)?
Only by video? No good. But in the hands of a competent instructor, they will pick up things on videos that many other will miss.
My instructor tells us a story about when he was injured and could not train. He would watch aikido videos and watch them frame by frame. Hand position, footwork, angles of entry... so much did he gain from doing this that he can spot mistakes we make that are so subtle... and fix them before we develop bad habits.
Video is a good medium. You can watch the same thing over and over and pick up something new almost everytime. It has value, but is certainly NOT the sole teacher by any means.