If you are doing an even effort, you shouldn't be building lactic. It means you've gone anaerobic.
Any reasonable effort (well below where someone would TT) will produce lactic acid. Whatever definition of lactate threshold you choose (4 mmol/l, 1 mmol/l above baseline, etc) will represent a significant production of lactate. And remember, functional threshold is an even higher effort. Also, aerobic/anaerobic isn't a switch where you move from one to another. There is a continuum of metabolism and both will be active at any TT effort.

Production of lactate != lactate buildup. The trick is to produce at the correct rate so you don't start buildup.

Any reasonable effort (well below where someone would TT) will produce lactic acid.

Absolutely correct. I was being overly simplistic.

Hate to go "assuming" again, but the OP's post states that the lactic would have to be "dealt with", inferring an effort that's gone past (or well past) LT. I suppose "overproducing to the point of not clearing lactic" would have been much more accurate.

I stand by my "$crewed the pooch" statement in that context.