In our run the other night, before the devouring phase started, adds never stopped (maybe I just don't clearly understand WHEN they come out re: his health). Once the devouring phase started, they eventually stopped and we could clear until it was just skolas. Same with mines.
The fight just isn't worth it as it stands and the margin for error is next to 0. I enjoy a challenge, like with HM crota when it first launched, but the rewards for this entire encounter (including the first 5 rounds) is laughable.
The adds are definitely directly tied to Skolas' health. If your team holds off on taking out the servitors, and clear the adds, you'll have an empty battlefield sans the servitors and Skolas. Then kill one, damage Skolas, and trigger the next add wave. That's what I've done on every run so far. We spend as much time with an empty battlefield as with one filled with adds. It sounds like not knowing this meant you had too many variables to juggle, which makes it much harder.
On all but one of the Skolas runs I've done, we had at least one and sometimes two newbies, and we cleared without a single wipe on a couple of those. It's a very doable encounter as designed, but you have to know the mechanics and develop a strategy, and keep in constant communication. But Lightswitch in the mix is absolutely excessive.
The Skolas fight is my favorite activity in the game so far (on non-Lightswitch weeks). It's resulted in some of the most satisfying, exhilarating moments of teamwork I've ever had. (It's also resulted in some of the most frustrating - two failed runs on Lightswitch weeks.)
Ok? You see people this very forum that spend countless hours on it and still don't finish it. So.. where does that leave us?
Not. Worth. It.
It's an encounter that requires you to know the phases and mechanics, have tight teamwork and communication, and encourages a mix of subclasses. The best runs I've had so far featured a defender Titan, a bladedancer Hunter, and a sunsinger Warlock. A couple of all Titan runs failed badly.
The main thing is, do it for the fun. If the fight is not fun, then no amount of reward is worth it. I've run Skolas on characters that had already cleared it for the week because I enjoy the fight. But I'll never run a Lightswitch week again, after that last attempt.