Spears are so hipster. They suck and the only reason someone would use one is if they were a warrior or liked sucking in comparison to good dagger rogues. It's like seeing a guy walking around with a walkman while you're scrolling down your iphone. Why would you choose to be inferior? By good I mean none of the dex is king, ss is king rogues.
I did some math comparing my shadow focus(FOCUS) spear to my dragonlord dagger at 5 str base (with garanak set)
Shadow spear is 2900 weapon speed x .60 (60% haste)= 1740 speed
2900 -1740 speed (you're subtracting the 60% to find the actual speed) = 1160 speed or 1.16 seconds per hit.
Dragonlord dagger hits the weapon speed cap at 1s per hit on haste or 1000 weapon speed.
Damage: 2715 with spear and 2096 with dagger.
To find the "damage per second" all you need to do is divide the damage by the attack speed, so it came out to
Spear: 2340.5 dps
Dagger: 2096 dps (obviously)
...Ofc this is before any strength is added at all, which will increase the differential because the spear will get more damage per strength point than the dagger (65 more Pierce Damage)
My personal opinion for an end game str rogue (which I assume you are based on your mocking of dex rogues) would be to use spear. You could still use sneaky, just switch to a dagger for the 1 hit every what... 30 seconds? (Idk I don't use it
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) to maximise dps