First of all, this is nice because going from a 456 delay 7hit build to a 456 delay 6hit build is an increase of ~16.66% WS frequency.
456 * 7 = 3192
456 * 6 = 2736
3192/2736 = ~16.66% more WS frequency with the 6hit.
Ok, now to clear some things up:
With a 456 delay Kalavejs +1: You need +42STP for TP and +40STP for WS, for a 6hit build (6hit/5hit rebuild).
Math:
11.5 + [(456 - 450) * 1.5 / 30] = 11.8 Base TP per hit.
11.8 * .42 +(11.8) = 16.7 (16.7 TP per hit with 42StoreTP for TP)
16.7 * 6 = 100.2% TP (when going from 0% TP, need 6hits)
11.8 * .40 + (11.8) = 16.5 (16.5 TP from WS with 40StoreTP for WS)
16.7 * 5 = 83.5 TP (for 5 melee hits)
16.5 TP + 83.5 TP = 100% TP
So, looking back at Gradd's OP, you don't need to WS in white tathlum. You do need to WS in Aurum cuirass though. (At least with the gear that Gradd posted in the OP, I'm not counting Goading belt or the new STP boots etc.)
Possible gear sets for this 6hit build(6hit/5hit rebuild) would be:
For TP: /sam, rajas ring, Aurum cuirass, brutal earring, rose strap, white tathlum, and the Kalavejs +1 with +8STP. This gives you +42STP for TP.
For WS: it would be /sam, rajas, Aurum cuirass, brutal, rose strap, and the Kalavejs +1 with +8STP. This gives you +40STP for WS.
Another option could be:
For TP: /sam, rajas, Askar body, brutal, rose strap, white tathlum, attila's earring + ecphoria ring (or chivalrous chain), and the Kalvejs +1 with +8STP. This gives you +42 STP for TP.
For WS: it would be /sam, rajas, Askar body, brutal, rose strap, white tathlum, and the Kalavejs +1 with +8STP. This gives you +40STP for WS.
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Now, let's look at a 5hit build with Kalavejs +1 and Eisen grip:
456 *.24 +(456) = 565 delay
Therefore, with a 565 delay Kalavejs +1 (while wearing Eisen grip): You need +37STP for TP and +34STP for WS, for a 5hit build (5hit/4hit rebuild).
Math:
14.5 + [(565 - 530) * 3.5 / 470] = 14.7 Base TP per hit.
14.7 * .37 +(14.7) = 20.1 (20.1 TP per hit with 37StoreTP for TP)
20.1 * 5 = 100.5% TP (when going from 0% TP, need 5hits)
14.7 * .34 + (14.7) = 19.6 (19.6 TP from WS with 34StoreTP for WS)
20.1 * 4 = 80.4 TP (for 4 melee hits)
19.6 TP + 80.4 TP = 100% TP
One possible option for this 565 delay 5hit build(5hit/4hit rebuild) would be:
For TP: /sam, rajas ring, Aurum cuirass, brutal earring, Attila's earring, and the Kalavejs +1 with +8STP. This gives you +37STP for TP. (If you don't have Aurum body, you could do Askar body + White tathlum here)
For WS: it would be /sam, rajas, Aurum cuirass, brutal, and the Kalavejs +1 with +8STP. This gives you +36STP for WS. (though you only needed +34STP for WS) (Also,If you don't have Aurum body, you could do Askar body + White tathlum here too.)
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Now, let's compare:
The 456 delay 6hit build Vs the 565 delay 5hit build.
456 * 6 = 2736 delay to 100% TP
565 * 5 = 2825 delay to 100% TP
2825/2736 = ~3.2%
The 456 delay 6hit build Kalavejs +1 has ~3.2% more WS frequency than the 565 delay Kalavejs +1.
Additionally, the 6hit Kalavejs +1 also does one more melee swing on the way to 100% TP, while still being faster than the 565 delay 5hit Kalavejs +1.
The 456 delay 6hit build Kalavejs +1 is clearly better... than a 565 delay 5hit build Kalavejs +1 (565 delay is from wearing Eisen grip).
Also, just as some other people have already mentioned, the Goading belt, and/or the new Ace's Sabatons could make this build easier to make.
Further, new possible storeTP gear for drk, as well as a possible "Kalavejs +2" with more StoreTP...on the next update, would also make this GS 456 delay... 6hit build easier to make.