To be honest I think it was a bunch of things:
1. random mode, the problem here is that I don't have much problem with random so it might be a bigger factor than I think it is... then again, last weekend, we got really bad picks compared to them, they always got air or storm or tc. And comp tc differs a lot from human tc. Even the races... remember the orcs! ugh
2. In lesser extent the new heroes AIs, dread shaman worked really well since from the dawn of your versions they can't stop bunching.
3. Their itemization changes, I think swash got all the items from the start so he was rather tanky in all the games, and I/we? though he was the easy target but he could withstand a lot of damage. Plus now he abuses the roots orb to gank or escape and it works really well for him.
Now that I think of it, the problem of them, the ai spellcasters, getting evoker is that anyways they will get the items, because they have better income (insane AI). I suppose this means that scaling well (again because insane AI) plus evoker makes them scale even better.
But in my opinion the MAIN problem is the bunching, every time we happened to get one or two alone, I was fearing for the others to show up in no time, and I think they did every time, then they started ccing us or healing the hero that was alone and finally they got away or they just overpowered us. Another thing about the bunching is the lack of defending other locations, when we split up to attack multiple places, they just kept going on the lane they were bunched and destroyed it. They get away siegeing early on, like it's nothing, I don't know if we can do the same.
In the past in storm if all of them were bunching on one lane, we just went to an obelisk/s and they stopped and went to defend it/them. Now they just ignore it and keep going, moreover if it's something like mid lane in stormwail where we are destroying their obs, once they finished they current lane they'll comeback and bunch + merc mid. Thinking about it more and more... in last weekend games, army from the cores didn't even play a big factor, they were ahead of us early on.
Conclusions... they teamwork better than us...? ... Their base "trade"/oneshotting race strategy works really well...?
PD: I suppose we will have to play normal comps from now on
or dunno tone down their straight cheating?