[Saavedro]

It's not possible for the pool to hide what chain it is working on from its miners. If you're connected to the ES-pool when it is working on the mainline chain and you see it start working on top of a block that is not on the main chain, that's a good indicator that it is a block ahead of the main chain.

If you see it work on top of yet another block that is not published, it's probably two ahead, and so on.

You of course, can't just connect and immediately know, but if you watch the pool (as a miner) you can figure it out.

[GhotiFish]

Ah. I see, your right, in that way you can know it's ahead, but can't spoil the advantage. Thanks for pointing that out.

So I was wrong.