disaster struck. And while I knew that the two coldn't be related I was still a bit gun-shy. However, after being unable to restock my chess sets for a day I decided it couldn't put off my Makerbot maintenance any longer. So I disassembled my extruder head, got at the feeder screw, brushed off the caked on plastic, and reassembled everything.
Fortunately this time nothing happened and I'm back to printing. Thank heavens for small miracles.