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yep, tiny nitpick: funding isn’t really fees to the exchange, it’s a transfer between longs and shorts, so your incmoe is someone else’s outflow :)
If you stay neutral with cash and carry, you can clip funding, just watch rate flips and clamp rules.
Also factor maker taker costs and ADL risk, they can eat a chunk, definietly on high leverage.
you running it delta neutral or taking directional swings?

Exactly, if I said that, it was an error. Thats one of the core principles is the flow of cash to traders.