I think that running the operating system from USB would slow things up anyway.
To really test this you need someone who has a dual boot system with both Linux and Windows on the same HD, that way both Linux and Windows have equal hardware resources, if not many other factors will come into play.
wow!! you did this long ago.
even i worked as an Linux admin from 2004 to 2012, i kept using windows for art stuff.
when i switched to blender from XSI Zbrush, I had to force myself replacing photoshop with gimp, illustrator with inskcape, premiere with resolve and bye windows.
recent years i was a dev for a company that uses visual studio so i was using windows at work a lot