Next, let's look at line 129, the Elf Ranger 11 Stormwarden Twin Strike Scimitar 19/22. For his base damage, the damage range is +2 weapon, +1 weapon spec and +1 TWF, and 1d8 weapon damage to give 5 to 12 range. For his crit range, first we give the max 12 damage for crit, then add 2 W since this is a scimitar, a high crit weapon. This is the same as hit base attack, so this adds 2 X ( 5 to 12 ) = 10 to 24. Adding 12 for the crit, we have 22 to 36. Now we also add 2d6 for the frost weapon crit, giving 24 to 48.
You're counting the +4 to damage three times or something. The damage on a crit is 1d8 (base, maximized), +2d8 (high crit), +2d6 (frost), +2 (weapon focus), +2 (enhancement bonus). TWF is not counted (as noted in the first post), because it was complicating my calculations and is a minor bonus.
So the end result is 8 (base) + 2-16 (high crit) + 2-12 (frost) + 2 (weapon focuse) +2 (enhancement bonus), which is 16-40, as in the spreadsheet.
P.S. One high damage combination I didn't see is a rogue who forgoes his paragon path to steal the Ranger At-will of Twin Strike.
That's an interesting suggestion, and like all the rogues it will probably do well against low armor foes, but poorly against high armor foes. The reason is that, although you can get something like 3d8+str bonus backstab, vs 2d8 for quarry, you lose the scimitar dance (since backstab only works on light blades...)