You seem to be incredulous, and sure the first Province is too early, but why doesn't a deck where Estates have been changed to Silver, the low value treasures are being chopped by Counterfeit and has 6 Magpies sound good to you? I mean I guess you could call it Magpie BM but it seems to me that he's doing a lot more than that. I would have liked a Treasure Trove or two in his deck as well.
As for the engine, I dislike the first Herald and Plaza buys a lot, I'd much rather they were Magpies to try and win that split more. It seems like a tough job to try and trash fast enough here, but if you do get there the only way you can possibly explode powerfully enough to catch up is with a lot of Developing and Duplicating and playing stuff you gained on the same turn. I've really no idea if it works out though (the speed of both strategies depends on the Magpie split/luck. I think I like a 2nd Counterfeit before the Treasuries and there was at least one turn where Copper was trashed over Silver, but Silver would have gotten you to $8 and two engine pieces.