Blackbird: Bitcoin arbitrage

Why not run arbitrage on ETH etc. which have far shorter transaction time than BTC. That surely is a much safer bet with essentially the same API. With the current transaction time BTC arbitrage doesn't seem to be a wise idea at all. In between the several hours the price could have easily changed more than 10%.

This doesn't actually ever send coins over the network. It shorts on one exchange and goes long on the other.

As such it is market neutral (since prices should converge) and transaction time doesn't matter.

Still doesn't work too well.

In particular "prices should converge" is hiding a pretty big precondition in very few words. You don't only need prices to converge, but you need them to converge within a reasonable time span, which is obviously not guaranteed. (because if the market was efficient already then the prices would have converged already and it would not be feasible to run arbitrages like this)