OK, I hope this makes sense to someone: I left Console running had up screen under Log Files - system.log
I put it to sleep at 17.33.34 and then woke it up with the 'chair' method and this is what it said:
Mar 2 17:33:34 simon-brookes-imac-5 kernel[0]: System Sleep
Mar 2 17:34:05 simon-brookes-imac-5 kernel[0]: Wake reason = EHC1 EHC2
Mar 2 17:34:05 simon-brookes-imac-5 kernel[0]: /drv/ MacDevice.cpp:561 com_parallels_hypervisor_client:

owerDownHandler: message e0000320
Mar 2 17:34:05 simon-brookes-imac-5 doubleTwist[18171]: State:/Network/Interface/en4/Link (up)
Mar 2 17:34:05 simon-brookes-imac-5 kernel[0]: System Wake
Mar 2 17:34:05 simon-brookes-imac-5 kernel[0]: /drv/ MacModule.cpp:261 powerStateWillChangeTo: flags=82 stateNumber=4
Mar 2 17:34:05 simon-brookes-imac-5 kernel[0]: /drv/ MacModule.cpp:262 powerStateWillChangeTo: found flag=kIOPMPowerOn (2)
Mar 2 17:34:05 simon-brookes-imac-5 kernel[0]: /drv/ MacModule.cpp:267 powerStateWillChangeTo: found flag=kIOPMRestartCapability (80)
Mar 2 17:34:05 simon-brookes-imac-5 kernel[0]: /drv/ MacModule.cpp:261 powerStateDidChangeTo: flags=82 stateNumber=4
Mar 2 17:34:05 simon-brookes-imac-5 kernel[0]: /drv/ MacModule.cpp:262 powerStateDidChangeTo: found flag=kIOPMPowerOn (2)
Mar 2 17:34:05 simon-brookes-imac-5 kernel[0]: /drv/ MacModule.cpp:267 powerStateDidChangeTo: found flag=kIOPMRestartCapability (80)
Mar 2 17:34:05 simon-brookes-imac-5 kernel[0]: Previous Sleep Cause: 5
Mar 2 17:34:05 simon-brookes-imac-5 kernel[0]: USB (EHCI):Port 1 on bus 0xfd has remote wakeup from some device
Mar 2 17:34:05 simon-brookes-imac-5 doubleTwist[18171]: notifyNetworkInterfaceChange requested (deferred)
Mar 2 17:34:05 simon-brookes-imac-5 doubleTwist[18171]: IPv4 Dict: (null)
There's more stuff at 17.34.12 onwards but since the mac is already well awake by then, I doubt you'll need it all.