Chris,
Thanks for the insight and sharing your past learnings.
Not as much with RUT/SPY/GLD, but more with individual securities, liquidity has been the main factor on many of these trades as I have allocated more of my portfolio to non-directional trades, especially when trying to minimize slippage on these 2 and 4-legged trades. A lot different than my directional "mindset" where a few pennies here and there weren't material to the results. The pennies are significant on these $1.00 to $5.00 non-dir trades, but meaningless if you can't execute. Still getting a feel for those trade-offs.
FWIW, i decided to close the GLD calendar Friday and take the loss.