Quote from atticus:
There is nothing magical about gamma-trading into a fly. The position ceases to generate deltas at the wings, so it's not as though the diminished theta (over a straddle) somehow increases the expectancy.
I know a guy at the Nymex who made millions over the years in long vol and scalping gammas. In 2008 he went in huge (Ks of contracts) on a long atm CL straddle when vols were in the top decile. He was confident the vol would continue to break out. Not only did he miss many scalps by pennies, but the contract pinned to his straddle-strike at expiration, taking him out of the game.
I think Spartacus's example was about a long straddle.Quote from jones247:
If I understand correctly, the Nymex guy made millions gamma scalping the flys (particularly a Reverse Iron Butterfly). Nonetheless, in 2008 he got taken out of the game [does this mean that he lost millions]... why did the flys not protect him from a IV collapse??
Quote from atticus:
Fair enough, but how do you arrive at the belief that a straddle's theta is double?
Quote from atticus:
There is nothing magical about gamma-trading into a fly. The position ceases to generate deltas at the wings, so it's not as though the diminished theta (over a straddle) somehow increases the expectancy.
I know a guy at the Nymex who made millions over the years in long vol and scalping gammas. In 2008 he went in huge (Ks of contracts) on a long atm CL straddle when vols were in the top decile. He was confident the vol would continue to break out. Not only did he miss many scalps by pennies, but the contract pinned to his straddle-strike at expiration, taking him out of the game.