For now, I will simply blame the non perfect physics for being 1.5 seconds per minute off the pace. I try to make reasonably believable setups, and I'm a Driving God of course, yet I still loose time.
Then I see a WR and disagree with how those times are achieved, both looking at the setup and the driving style.
Once I have all the WRs, the physics are completed and I will instruct Scawen to stop working on them......
But seriously, yeah there are some oddities, not the least of which is the diffs. However I suspect the reason we get away with them is in the tyres.
The fastest laps look odd to me, almost like slow motion, the (road) car rarely being snappy or having trouble to accept the attitude desired by the driver.
I'm not sure LFS is advanced enough yet to call for the use of realistic diffs. Mind you its pretty advanced; but tyres are so tricky that the chances of a few fair flaws still being there are considerable.