The project box was in PLA, but I've had similar problems in both PLA and ABS. I had already learned to turn off retraction if there are lot of very short segments (legs, posts, etc.) involved in a print, but the corner-to-corner travel on that box had me fooled. I edited the post to explain how I had travel and printing both set to 100mm/sec, so I didn't realize that some of the movements were just travel (why didn't I look at the extruder gear??). That box was probably on my "worst" spool of PLA for this. It is softer and more pliable than my other PLA and ABS, and it's undersized in diameter. Variables like that are probably more significant than PLA vs ABS.