my favorite online resource and asked them what's up and within a day I had someone point out that my brand new extruder assembly had a larger toothed gear than the old one. And as anyone with a bachelors in math will know, a gear circle will extrude more plastic per rotation. So I had to adjust the feed multiplier rate.
Filament Diameter testers with 100% infill and different feed multiplier rates until the right one was found, which in this case was about 1.10, up from 0.93 of the old ones. Then I went to C:\Program Files\MakerBot\MakerWare\MiracleGrue and edited all the default xml config files with the new multiplier rate because I'll be darned if I'm going to use custom profiles on every print.
So now, now I'm really back to printing.
Any suggestions on what I should do with my old extruder assembly?