[Yoda]

Tiger, with his right arm only drill, is ingraining a hitters stroke (not a shoulder frame stroke). Is that correct?

Agreed.

That said, his Stroke is totally different once he adds the Left Hand to the Grip. Now, instead of pushing off the Right Shoulder with an extending Right Elbow, he freezes the Right Elbow and thrusts via the Right Shoulder Turn.

So . . .

What is the benefit of all his one-arm practice?

Right Forearm Tracing (Clubshaft Control) with the Lag Pressure Point (Clubhead Control). Only the Flat Left Wrist -- visual or geometric -- needs to be added (Clubface Control).

Once the aforementioned have been harnessed, the rest is a piece of cake.