I remember looking at this several times in the past. Sounds good except you would have to keep rebalancing every time one side gets too much larger than the other. Im thinking 10% or more is too much. I cant remember, it would take me a awhile to run some #s.
Then there are problems with shorting itself. Getting your shares recalled is likely during a sharp move. Then when you try to reshort, none are available. Most likely to the ETF your making money on during a sharp move.
Again I have no #s, but the risk of getting out of balance and then a big move against me on the larger posistion was too much for me.
I think if one stays on top the two pos, and rebalances when needed to keep near equal posistions, this might work out. If I read the TDA site correctly, I would pay 0 fees as long as I dont create a margin balance....then Im screwed. 12.50% margin rate LOL!
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