The touch screen on the ipad doesn't stop working entirely if the Apple Pencil is within 20cm or so, unlike Surface Pro 4.
As for pen and finger at the same time, I'd like to be able to switch pen size, zoom, press undo, or hold down a virtual modifier key with my left hand, but Microsoft's system blocks all non-pen touch input while the pen is nearby.
The example given of someone turning a dial while drawing a stroke... this could just be a touchscreen interface!! They're having to code it specifically to cope with the dial, but if the dial wasn't there and the palette was touch control, that would work great.