Instant poisons VI does (112+149)/2 = 130,5 damage per proc, 20% proc means you do on average 26,1 damage per hit from poison (excluding spellhit and resistance calculations)

Warblade of the Hakkari has 1.70 speed meaning 0,59 hits per second (0,76 hits/s with SnD)

CTS has 2.60 speed meaning 0,38 hits per second (0,5 hits/s with SnD).

0,76 - 0,5 = 0,26 extra hits per second for Warblade. 26,1 poison damage per hit means 0,26 x 26,1 = 6,786 extra poison damage/second for warblade.

However, the weapon dps difference is as high as 58,5dps - 47,9dps = 10,6dps difference, meaning that CTS compensates for lower poison damage with higher white hit damage with a ~4dps advantage

On top of that the stats on CTS is better, CTS gives 0,5% crit chance more while mandokir OH gives 12ap more. 12AP is slightly less than 1dps for mainhand (and most likely less than 3dps overall). 0,5% crit chance (assuming you aren't critcapped) gives you more than 3dps if you do at least 600dps on average while active, which is very easily reachable.

The conclusion I'd draw is that CTS is a better offhand sword than Warblade, is this correct? I ignored armor calculations but I also ignored poison resist calculations, would they change this? And if not, isn't VK/CTS then a better combo than CTS/Warblade?