Congrats Derek I also take the MMBW (only in the PM towards Boston) and it's a great route. I think you're right about the "false flats" it does seem to slightly ascend and descend. It's funny how just the slightest uphill is really noticable.

I try to not use any pack other than a small wedgie under my saddle which contains cell, wallet, keys, tire irons, patch kit, and spare tube. ALl that junk fits into a pretty small bag. Typically I'll drive to work one time per week and drop off a weeks worth of clothes. I noticed today I'm running low on socks so I'll probably stuff a few more pairs into my jersey pockets before heading out tomorrow.