Although hiding AlphaStar's identity was part of the experiment, it also seems a bit sneaky to try to hide the smoking gun of impossible actions.

The main impossible action that serves as an AlphaStar giveaway is that it doesn't use control groups. That by itself doesn't suggest an unfair advantage, though. It's just noticeable in replays. The APM still seems to be in line with high-level players.

If I remember correctly (from other games), control groups means that you can select a group of units and assign a number to them (Ctrl+n?) so you can then issue commands to them as a group.

I think that a human player's game would be significantly slowed down if they had to play without control groups. Accordingly, the ability to control units without having to assign them to control groups must be a very big advantage for the purpose of micromanaging units. It would be like playing a turn-based game when everyone else was playing in real time.

True, you might be right. It might be using an abstract notion of control groups internally (learned through watching and playing so many games), capped at the typical control group cap, in which case maybe it's not an advantage. But maybe it is able to have much more fine-grained control over every single unit, in which case it probably is an advantage.

It was also selecting buildings that for a normal player would either be out of the isometric field of view, covered by ui elements, or only barely on screen like clicking 1 pixel specific in the corner.

That's a big problem, and if true would probably invalidate the results. I would guess that AlphaStar was giving unrealistically complicated orders, or more likely tons of orders on opposite sides of the map simultaneously, a feat that would be all but impossible for a human.

You're overstating the issue here. Deepmind wasn't forced to control units using the standard control groups. My understanding is they could directly issue commands to arbitrary group of units. If you watch the replays, the APM/EPM is not too abusive. The main advantage is that it doesn't pay the cost of context-switching so it's very strong at multi-pronged attacks. It still didn't seem smart in the replays I saw on Youtube. Basically it's very good at developing mid-game timing attacks that humans tend to struggle with (not because of APM, but because it's easy to make mistakes when so much is going across the whole map).

I haven't played Starcraft II so I can't understand how well AlphaStar is playing, but if it has any sort of advantage other than its ability to develop a winning strategy, then it's very difficult to support any claims that it's winning because of its ability to develop a winning strategy.

It's a complicated matter because it's (claimed to be) the first system that's doing so well in Starcraft II so it's hard to believe it just has a mechanical advantage. But on the other hand, Google is in a position to throw a lot more resources on training their system than most others, so maybe it's just a combination of having a ton of compute coupled with a slight advantage in how you can control your units.

If that is the case we haven't really learned anything new from Google's achievement: we already know that a powerful computer can do some things faster than a human (e.g. arithmetic). We also know that there are things that humans can do a lot faster and better than computers (e.g. learn human language). The question is if Google's system is getting better at something that computers are known to be not very good at, in this case, strategy, I guess. That would be something new.

Personally I'm still in my default position which is skeptical.