Re: fighting tall question
One thing you do not want to do is punch down at a shorter opponent; that doesn't keep him at the end of your reach, it shortens your reach and gives him opportunity to punch over the top. If you watch Bob Foster in the video, you'll see how he does a bit of both things mentioned. He lowers himself by widening his stance, and he jabs from where you should be jabbing from, about chest level.
http://www.youtube.com/watch?v=Q-1Kig4wjKw
For some inane reason, the trend in today's version of boxing his too hold your hands far too high. Your lead hand should be chest level to keep it out of the way so you can counter with it. Your rear hand should be responsible for 80% of your defensive work and your lead shoulder should take up the bulk of the rest.
Re: fighting tall question
I think you already answered your question in your first sentence op.
It would have to depend on the fighters style.
If you have a tall outside fighter hes not going to want to lower his head and put it in closer range to a shorter inside fighter.
If you have a tall natural inside fighter then he would want to lower his center of gravity and work on the inside.
Re: fighting tall question
I always go to the body on tall guys