In this case, the manager knew enough to know the person was spewing BS objections most of the time. He was actually an expert in the field and the discussions were often of a technical nature related to his expertise.

Although yes, it was a separate problem that he didn't know plenty of the operational "small" details which caused him to always underestimate project timelines.

What does TPS stand for in this context?

It's a reference to the movie Office Space. https://www.youtube.com/watch?v=Fy3rjQGc6lA

Actually I think it's a reference to one of the principles of the Toyota Production System (TPS):

A leader must understand the daily work in great detail so that he or she can be a best teacher of your company's philosophy. -- https://missiontps.blogspot.com/p/14-principles.html

That's different from the TPS reports of Office Space fame (https://en.wikipedia.org/wiki/TPS_report).