Dear John,

The micrototor is indeed the core of Calibre 11 and 12 and still remains nowadays a pretty unique and rare device compared to the oscillating mass used by most chronographs. The only drawback of the historical micrototor was an inferior re-winding power vs a mass. Nowadays with new materials though this could be corrected by using an higher specific mass allowy allowing to get more efficiency. Still it would not fix the second issue i.e. more thickness vs a mass leading to thicker-bigger chronos. But why not as big chronos are very trendy these days. Thanks for the idea. We should stress more the microrotor anyhow.