If there was debriss on a section of the sheave the hat would explain the abnormal tight section but as I stated, 180° from the tight section is the loose section.
The other two sections are the average
This could still be consistent with grime in the sprocket teeth. An easy check is to set the rear wheel so the tension is highest and examine the rearmost section the sprocket to make sure the belt is uniformly sitting in the sprocket.
Hey, who's garage is the Beast parked in?
One last attempt to convince you that this is a manufacturing &/or assembly issue.
As viewed from the left side of the bike with Approximate positioning:
When the valve stem is @ 4:00 the belt is its loosest & @ 11:00 its tightest.
2:00 & 7:00 are neutral/average.
This pattern also corisponds with 2 of the 4 sheave to wheel mounting screws being in alignment with the front/motor sheave.
I recommend that all owners &/or mechanics check the belt tension at these coordinates (& perhaps even halfway between these 4, i.e. 8 total locations) to insure that the rear sheave is properly manufactured &/or installed.
My belt tension (2016 DSR) varies approximately 20 Kg's.