Quote from jones247:
Hi Thinkplus,
I chose a long term spread (i.e. Dec/Jan) because of the option price convergence between the two months.
...
I am actually testing this method, not just discussing it.
I am not sure which quotes you are referring to, and may be I am not clear about your objective, but let's consider the basic premise of the strategy.
Calendar (and the related) spread strategy is a neutral strategy, that is expecting the underlying to remain in a range while we benefit from the time decay of the sold premium. Basically, you want higher theta while keeping the other Greeks pretty neutral.
Now you might be aware that option theta decays the most in the last 30 days or so. That means you want to sell the time premium which will decay faster than the one you have bought.
In your scenario, you are selling the spread for 6 and 7 months out. You will not see the immediate impact of time decay until the last 1-2 months (considering the underlying remains range bound), but you are planning to roll your spread by then, missing the whole point of the spread.
You can try out this in any options software (TOS or Optionsoracle), and see that spread theta is higher for near months (1-2, or 1-3) than for the farther months (6-7). You may have 6 month spread (buy 6 month /sell 1 or 2 month option) and continue rolling the short option (there will be higher delta/vega risk compared to having 2-3 month calendar).
You may use TOS thinkback feature to carry out your tests faster. Let us know your test results.