Yes it does. The level of the original track is duplicated at the output of Drumagog. Drumagog also uses that level to decide which samples to play. There are different velocity layers in (most) gog files. That way, when Drumagog is triggered by a light hit, it will play back a sample of a light hit. So it maintains the dynamics of the original and it does it with the appropriate type of hits. It also has multiple samples in each layer. That way, even if the drummer is very even, the hits don't all sound exactly the same. That adds even more to the realism.
Some gogs even have different positions. Like position 1 would be a center hit, position 2 would be an off center hit, position 3 would be a rim shot, position 4 would be side stick, etc...
So, making sure that you are feeding a strong signal to Drumagog is very important to getting the most out of it. BTW If you have a song that requires a softer touch, just turn down the signal feeding it. You will then be triggering the softer, buzzier (for snare) samples.