> That cannot be true almost by definition. Running a virtual machine of any description carries overhead which you will not incur running directly on the hardware.
A computer scientists might say that's true. A stopwatch will say the virtual machine is faster - much faster. You can easily see it for yourself by checking how long it takes to reboot while installing Windows updates. You can also explain it "scientifically".
You would agree, I'm sure, that a system with 8GB of RAM and a hard drive with 64MB of drive cache might be much faster than a machine with 8.01GB of RAM and 1MB of drive cache. Agreed?
We've established that a machine with more RAM serving as storage cache might be faster than one with less, even if the one with small storage cache has more RAM overall.
Therefore, a system with 6GB of RAM and 1GB of drive cache might be faster than either of the above 8GB machines. That's essentially what a machine running a VM is. From the perspective of the guest OS, the host hypervisor is firmware - firmware with a GB of cache RAM.
Also the hypervisor or host OS may simply do a better job of using the hardware, it may have better drivers. If the hypervisor has a very fast driver for the storage, while Windows has a slower driver for that storage, it may be faster to let the hypervisor talk to the hardware. Windows uses the virtual storage driver which should be extremely fast because all it does is map, or perhaps copy, RAM.
You can see a very clear of case of a virtualized copy of Windows being much faster than one running on metal by just installing some Windows updates that requires rebooting the OS. On metal, a full reboot may over a minute to complete all of the "on startup" processes. Within a hypervisor, the same processes may complete in under 10 seconds because everything is read from host cache RAM rather than from spinning platters. From a computer science perspective you might say "that's cheating, the virtualized Windows didn't have to actually reboot the hardware". Well no, it didn't. And that made it much, much faster. It's much faster BECAUSE it didn't have to reboot the hardware, but the first three words of that sentence are "it's much faster".