It's actually a more natural placement than the one required to type on a keyboard either in my lap or on a desk. My wrist is kept straight on both axis and th

It's actually a more natural placement than the one required to type on a keyboard either in my lap or on a desk. My wrist is kept straight on both axis and there's no strain as both my forearm and hand are resting on and supported by a surface (e.g. my thigh or the desk). It's roughly equivalent to having my thumb on the CTRL key position which is also fully supported but in the case of a desk, thumb on screen offers more wrist support. Having my hand on home row is awful by comparison because my hand is completely unsupported and angled on both axis so there's a lot more strain.