in the days of the 65in wood, few hit that shot, the slice dominated.
in the days of 85in graphite, edberg, mcenroe, sampras, guga... the racket hits more thru the ball, and the conventional wisdom is - 'stay sideways thru impact'.... now that may work for somebody... but staying sideways thru impact would require a bigger turn in the backswing, thus longer set up time... and if the coil in the backswing is not achieved, you have no option but to arm the ball forward.
now we have better equipment, 95in minimum... the same theory of FH hitting across the ball can be applied to the 1hbh. like I said earlier, make sure the upper arm is connected to the right chest thru impact, so you don't rely on the arm muscle.. you rotate clockwise thru impact and you will feel solid impact even against the most vicious ball coming in.... and while your core rotates clockwise, your hand can passively let the racket drop and natually make the low to high swing path (I prefer this way for baseline rallies), or you can actively engage the forearm to exaggerate the windshield wiping. (I prefer this way for hitting dipping passing shots).
hitting this way also means you don't need a big turn in the backswing... just experiment a little.. you will find out that even with a minimal backswing, you can still hit solid shots... this is a great advantage when the ball comes fast.... watch wawrinka, mauresmo, schiavone, dimitrov... they all hit this way... notice how much they open up thru the shot.