You are also making my point that your statement is completely biased by your assumptions going in. You assumptions are that the stock is going to make a large move in a relatively short period of time. If that is your fixed assumption than ANYONE in the option world will tell you to play the short term options. NO ONE would tell you to buy 6 months options if your expectation was a big move in 30 days. My problem is you are making a GENERAL statement based on your limited assumption.
Ok so we mostly agree fair enough.
I just want to point out that what you call bias is what I call a thesis. Also I want to clarify that the said thesis is opportunistic. That is, the thesis doesn't hold all the time for all underlyings. My whole point is that playing long gamma requires you to have a thesis that have a positive expectancy of return, and what that translates into is that the expected move should be at least as big as the implied move in the price of the option for a given time frame (being 1 day or the lifetime of the option). If that doesn't hold, I don't play the move with options, perhaps I look for shares or other linear instruments.
I however still have some disagreement with the following statements:
Showing the charts just confirms the theory of gamma that its peak is bigger for shorter term options which I already stated is true. However you have said long-term options have no gearing or serve no purpose. AGAIN your statements are all fitting into your assumption of 1 sigma move in a short time period. Also you never account for the fact that long term options have HIGHER delta and therefore the gearing is similar with smaller gammas.
In terms of LEAPS I repeat my position, LEAPS and in general long term options are inefficient ways to play an arbitrary move. I didn't want to imply they were useless just that other instruments could be used for that kind trade with better PnL and Risk Reward (like shares, CFD's or futures). When you are trading like that you only want leverage and for that there are many ways to get it other than options. Sacrificing optionality just for the sake of getting leverage is not a good trade-off at least in my book. However of course you are free to trade as you feel more comfortable.
.01 gamma on .57 delta (short-term) or .005 gamma on .61 delta (long-term). You are saying only the former has gearing but for a $1 move the further out in time option will move by a greater amount despite smaller gamma.
I think I can see where your mistake is, you are only thinking about the linear part (which is delta), but you are not seeing the non-linear component to this. Of course a 0.9 delta option will have a better *dollar* profit than a 0.5 delta option for a 1 point move. But you left out two very important things that are obvious from the charts that I posted:
1. The return must always be reported with respect to cost. It makes no sense of talking of $1 dollar profit if the position cost you $100 versus $0.5 profit if the position cost you $10
2. Take gamma into account, a 0.57 delta option will accelerate really quickly in price, eventually reaching 0.9 deltas if the move is big enough, whereas a 0.9 delta option only has 0.1 more delta to go up.
That is why in the charts I posted, options with higher gamma *always* beat options with lower gamma for the same kind of move ( that should be self evident).
AGAIN we are not disagreeing, your UNIVERSE though is only 1 sigma move in 30 days so naturally you discount anything beyond front month options. That is not rocket science.
My universe is very general, however I agree that if I play long gamma with options is because I think the expected move in the underlying will be higher than what is priced in the options for a given time-frame. It doesn't matter if my view is for 1 day or 120 days, if the expected move is lower than what options are pricing then why give my money away to the option dealers?
This just boils down to the basic concept that an options play should only be done if they are mispriced (that is where the edge is). And mispriced for long gamma should be understood as options pricing a move that is smaller than the one I think we'll get (for a given timeframe). If there is no misprice I don't play the move with options. Of course I'm not saying that that is the only way to play trade options but I think that is the most efficient way.