Re: [ANN][CLAM] CLAMs, Proof-Of-Chain, Proof-Of-Working-Stake, a.k.a. "Clamcoin"

The small purchases are made to cover loses incurred by the short-selling (if price goes up after a short-sale, the portfolio has lost 'value', and must purchase CLAM to cover that loss).
At least, that is my understanding of it.

Small price changes normally wouldn't cause margin calls. You have to lose enough to drop below the minimum required equity first. Of course that depends how leveraged you are. Poloniex allows something like 4:1 leverage I believe, though some of the BTC margin exchanges allow some really crazy stuff like 50:1 or maybe even 100:1

Conceptually that is correct though, right?

The purchases need not be small, necessarily. If the market moves a lot and the position is large (and especially if highly leveraged), then large trades may be generated by margin calls. I don't remember exactly how Poloniex does margin calls either, but my vague recollection is they consider liquidation price which means orders coming off the book can trigger margin calls even if the current market price does not change. Don't quote me on that though.