Force of habit/inertia ? ...or possibly that its variance isn't large regardless of base system config
As it happens, I was just going on recollections from reading reviews...but since I had a spare fifteen minutes, I pulled up the latest reviews from the general sites I have bookmarked and padded out with a few other generally well known sites. Of the 37* producing a review on a regular basis, here are the benchmark occurances:
27: Metro 2033
26: AvP
24: 3dMark11
22: Unigine Heaven
15: Far Cry 2, BF:BC2
14: Vantage, Lost Planet 2
13: Mafia II (DX9 and 11), Just Cause 2
12: Crysis Warhead, Call of Pripyat, DiRT3
11: F1 2010
9: Civ 5, DiRT2
8: Shogun 2
7:Crysis 2 (DX11)
6: Battleforge, HAWX 2, Starcraft 2
5:Crysis 2 (DX9), Dragon Age 2, Resident Evil 5
4: Batman AA, CoD:Black Ops
3: CoD:MW2, Crysis, HAWX, L4D2
2: Bulletstorm, CoD4:MW, Stone Giant, UT3, Witcher 2, Wolfenstein, World in Conflict
1: Anno 1404, ArmA II, Brink, Chronicles of Riddick, FEAR3, MoH, Portal 2, Shift 2, Spinter Cell:Conviction, WoW:Cataclysm
(* bit-tech, TS, OC3D, Anand, Hexus, Hardware France, HT4U, Tech Report, Tom's, Madshrimps, OCC, OCAU, ABT, OCIA, X-bit, Tweaktown, TPU,[h], PC Per, Guru of 3D, Hardware Heaven, Hardware Canucks, Hot Hardware, Techware Labs, Overclockers.com, Legit Reviews, iXBT, eteknix, Vortez, Kitguru, Bjorn3D, Benchmark Reviews, Ninjalane, Hi Tech Legion, Neoseeker, Motherboards.org, Hardware Secrets)