My wife recently noticed that our guest bedroom wasn't heating up with the rest of the house, and after running my hand over the heat register to see if any heat was being pumped in (it wasn't), I donned my dungeon-adventure gear and headed down into the chasm again.

Apparently, I didn't do as good of a job sealing up the vent as I assumed the last time around, so I spent about 45 minutes re-taping the vent. Hopefully it stays put this time.