Question about Str/Luk shadowers

lvl150 LUK vs STR Shadower:

LUK:
180watt
923luk
160dex
Damage Range: 3652 ~ 6404 > Average: 5028

STR:
195watt
884luk
160dex
Damage Range: 3657 ~ 6383 > Average: 5020

These ranges aren't quite right...
LUK
180 att
923 luk
160 dex
46 str (obviously the difference is in base str?)
= 3601-6351 -> 4976 average

STR
195 att
884 luk
160 dex
85 str (75 plus 10 from a khanjar? hell if i know)
= 3828-6683 -> 5255 average

5.6% advantage for STR shadower at 150.