I'm glad the Medic Melee topic came up.
As a medic, it's frustrating whenever someone gets angry that I whip out my ubersaw on certain occasions. Now, I completely understand that it is my role to heal and uber, but sometimes, it is much wiser to get out your weapon and burn someone down as opposed to watching your healed target die. In certain situations, its a sad truth; your target will die no matter how much you hold your medigun on him. In those situations, a surprise attack with your ubersaw can either turn attention on you, or a crit from your saw could turn the tide of the battle- the enemy dies and your ally lives.
Medic is one of the most versatile classes, and really requires players who can calculate damage quickly and act accordingly. There are things that go unnoticed by the normal player that great medics do. For example, if I notice that my teammate is going to die while I'm healing him, I'll try to jump in front of him and absorb a little bit of the damage to help him escape around a corner. Most players will just assume that the enemy missed, but no, the medic put himself in more danger to ensure your safety.
GOOD medics are players who realize what is going on everywhere around them, and have a quick enough mind to be able to calculate possibilities, and know what to do if they arise. That's what I see separates the good medics from the healbots.