> It's usually almost impossible to tell but by probing at the extremes and forcing the system to do things that never happen under common usage, it's possible

> It's usually almost impossible to tell but by probing at the extremes and forcing the system to do things that never happen under common usage, it's possible Yes, but it's only possible by comparing the results to those same results when that action is performed outside of a VM. If you can never baseline your data outside the VM, then you'll never know you're seeing odd results. You'll just think "that's the way the world works".