Even the slight chance that your accuracy would drop below cap is more of a reason to use heca than alky's for any multihit. Acc drops on multihit WS will always result in more of a DoT loss than the str will ever make up for in a DoT gain. I may be talking out of my arse, but I'd wager losing one hit out of 100 WS ws swings (33 KJ/RR uses) because of any acc loss would completely negate any str gain.
I'm pretty sure you are talking out of your arse, at least as far as KJ is concerned - STR+4's effects work out to be somewhat more than 1% additional damage. (It's a guaranteed +2 to the modified base damage - +1 from fSTR, +1 from WSC. About 2/3 of the time, it's +2 to WSC instead. Even in a massive STR+ build, you're not hitting a modified base damage of 200+. Perdu + capped fSTR [STR 135] = modified base damage of 169. You'd need 208
STR to hit a modified base damage of 200, which ain't happening even with Alkys.)
Anyway, going slightly further in-depth, in scattershot manner:
First, the -DEX won't affect the first hit of each WS (in terms of accuracy, at least - for RR it's still a bad idea because it potentially screws with your crit rate). So, out of every 100 WSes, you'll have roughly 200 * (1+DA) hits that are
+2 to modified base damage in a "normal" WS build (STR 120?) is a slightly more than 1.25% increase.
Calling the average damage per hit N, you would normally see a total damage over 100 WSes of (95 + (HR)(200)(1+DA))N. From here on out, I'll assume a 20% DA rate and a 90% hit rate, which gives us a total of 311N damage.
With the damn-the-DEX-full-STR-ahead build, you instead have (95 + (.9-X)(200)(1.2))(1.0125N) = (314.89 - 243X)N. For this to be equal to the preceding one, X would need to be ~1.6%.
Net conclusion: STR+4 is worth missing slightly less than three extra hits out of every 200. Edited, Sep 11th 2009 5:45pm by MDenham