Since this is up again.
I made some experiments involving tc and koth earlier this month.
The cap layout is the same as hydro, one cp per area, 2 cps in play every round.
I implemented the two koth timers and set the timer to 1:00 minute. Your clock will only count down while your team owns both cps. The capture time is 0.5 seconds (translates to 1 sec cap time for non-scouts)
If each team owns 1 cp, neither clock counts down.
For final rounds, unlike regular hydro logic, the defenders can cap the attackers point, and as you'd expect this is how you'd succeed in "defending" the round.
Attackers only need to own both points for a accumulated period of 20 seconds though, while defenders still need the full minute.
I tried many ways to just have 1 cp enabled in the last round, and more or less have it be regular koth, but where the defenders clock started ticking automatically on roundstart (and was set to like 2-3 min) but it just kept crashing, gave up after many hours because I couldn't be arsed to look further into it.
So what does this solve? No idea, I just wanted to build a multi-cp koth thing, which was surprisingly easy.
Maybe the unexciting rounds where both teams just run past each other and races to see who captures first.
The layouts would have to be built to favor attacking, heavily. If it's too turtle friendly a round could go on for hours theoretically, as there is no third 'round' timer in koth. I doubt it would work using hydro and just swap the game ents. It's too easy to defend on that map.