[Tru_in_Blu]

The ball hitting the fence does not equate to the ball hitting the ground.

It most certainly does. Since I'm in NH, I'll again refer to Fenway Park.

You've no doubt heard the term "wall ball single". This happens when a ball is hit so hard it bounces off the left field wall and is caught directly off the wall or picked up after it has landed on the ground. The batter has no chance at extra bases, although in a different ballpark, it may have been a HR. This basically becomes a "ground ball" by definition.

A ball in flight that hits the top of the bullpen wall in right field and then into the bullpen is a home run.

If a ball in flight is deflected by a fielder or by his glove or head (thinking Jose Canseco here) is a home run.

If a ball in flight is contacted by detached equipment (e.g. a thrown glove) it is a delayed dead ball. The play is allowed to continue. If in the umpire's judgement the contact prevented the ball from going over the fence, he can award a home run. Otherwise, if the batter does not reach at least 3rd base, the runner would be awarded that base.