Okay, I checked again. (Win10 drives me crazy because some things are in old Windows 7/8 locations, while other like-things are in new Win10 locations.)
I checked the old Control Panel > Turn Features on/off list. I was looking for "Hyper-V" there, but didn't see it. Then I noticed "Virtual Machine Platform.". But its box is not checked in the list. (So when you say that you have Hyper-V enabled in Features, do you mean Virtual Machine or actual Hyper-V?)
Nevertheless, all the Hyper-V services are listed in Services. (Per Black Viiper's list too.) They're all in Manual. None of them are running, even when I run IGCP.
So I don't understand - it seems like Hyper-V doesn't have to be running, but the components for both the main and guest components have to be there. (If you want to confirm,
Clanger, you could do a quick removal in NTLite Live to confirm that that breaks IGCP.)
I do not have Hyper-V Compatibility set in NTLite. I had not 'Lite'd this particular instance of Win10 yet. But this wasn't a fresh version of Win10 either. My logbook shows that I had been in Features earlier with this build, removing IE11. If Hyper-V was checked then, maybe I unchecked it but didn't write it down in my log.