I noticed last night that the 2nd attack in my Lancer's combo attack is always doing the most damage. The tooltip indicates that the 3rd attack should be the strongest. I'm not sure if my third attack is doing less damage than it should, or if my 2nd is doing too much. Any other Lancers notice this?

I just did a fight to get numbers, my first Combo Attack does 316, followed by 564 then 466. The tooltip says "Successive strikes do more damage, up to three hits, with the third hit dealing substantially more damage."

So again, clearly the numbers are bugged. It'd be nice to know how so, and if this is common among Lancers.

There's no bugs here. Your last attack hits more times and does more total damage.