Just a one case. Another - is large movements. Imagine a 5% drop. You will hedge every one minute and will not collect any substantial gamma....
Multicharts or Omega. The idea is that if you think that some hedge is better than other (say 1 min is better than 1 hour) you can not buy...
Let me tell you about my research if you get realized vola in day period smaller than in intraday constantly - its a simple arbitrage...
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