True at TDA where he trades, not true at Interactive Brokers where I do.
Um, are you saying that IB allows you to borrow money inside a retirement account?
TDA will happily give you a margin account, or a retirement account, but not both - and I believe that's in accordance with Fed. law.
You don't seem to be mentioning any trades that lost money
Well, the markets have been pretty bullish... and given that it's a retirement account, short selling it's an option.