[Yoda]

So am I correct in assuming that to achieve the proper feel of lag pressure, it is the player that is resisiting the club's change of direction, and that feeling of resistance is what we are to carry through impact? If that is the case, would it also be fair to say that overacceleration is the problem of applying more resistance than is needed to establish and maintain the proper pressure through the swing?

No, Bigwill, it is the Clubhead that resists the change in direction, not the player. The player establishes that resistance -- the Lag Loading -- in the Start Down. Properly manipulated, the Clubhead Inertia can withstand all the Lag Pressure we humans can generate. Homer Kelley described the phenomena (of incredible #3 Lag Pressure Point Pressure) this way:

"Sometimes I felt that if I were just a little stronger, I could have lifted both my feet off the ground."

Throwaway and its Over-Acceleration are the products of an improper, throwing pressure (typically from Pressure Point #3), not the steady, driving pressure of the Clubhead Lag.