If I push the filament through the hotend quickly, it moves easily. If I let the filament sit in the hotend for a few seconds, with the nozzle off, then it becomes stuck. This is what is happening when printing I believe. The extruder is pushing hard, but the filament is not transferring that pressure to the pool and very little extrusion is resulting due to the filament sticking in the hot end. Prints are thus impossible to complete.
I did not have this problem with the v1 hotend. I did have the problem of the v1 extruder grinding the filament and failing to feed however. Upgrading both has led to the current situation. I'm fairly familiar with the hand pressure on the filament required to generate a given amount of extrusion, at least with the v1 hotend, and the current pressure required is too much. Such that you can easily kink the filament if you are not careful.