I think he's trying to describe something like pairs trading, which works, but doesn't eke out much profit in flat markets, especially given the larger base of capital needed. Same issue that the returns would be decent on a few days but basically nil most days since springtime.

And this is without even considering why it makes literally no sense to spend some much time tracking small "deposits" with such exorbitant costs. That's the real problem with the scheme--not the difficulty of making profit, but absurd stupidity that would cause a hypothetical arbitrageur to buy leverage in the most expensive and time-consuming way imaginable.

Really? You have no money being held by BT that you hope to get back? You're promoting a service you yourself don't even subscribe to?