Evenly matched games are not the same at all levels of play. noob v noob, mid v mid, expert v expert. All are different. Just saying.
Well, we won't discuss noob v noob here: weird shit is happening during those matches. Most games and players I play with and against are mid+ by your US-centric taxonomy, I suppose That's perfectly all right, though a lot of them got much higher grades from Renz (was curious as to adequacy of my nooby impressions). However, some of the Russian guys (Dreamcatcher, Seawolf, Al-t, McLoover, Akumrise), Iz, doggu, ppapanek, renz are surely expert in my book. On that skill level (call it whatever you like), the same game flowchart I've witnessed in that second Zen vs McOrcenz match applies: the UB-less team is doing fine until late game, and can even have a good lead in kills and warscore, then the UB hits 15, and if he gets Bulwark - well, gg. If he doesn't, it just becomes harder, but still manageable. Good teams feed their UB items, though, so...