Bill Tindall, E.Tn.
Corrosive wear is the corrosion that occurs in the time scale of the planing stroke. Stroke, corrode, stroke- which removes the tiny amount of metal compromised by corrosion occurring since the last stroke. which leads to an insight...... there probably aren't enough planing stokes in David's experiments to remove significant material by a mechanism of corrosion followed by removal of this layer in the next stroke.
edit: did some calculations and I am less sure corrosion isn't fast enough to contribute

From Kato data the blade shortens at the rate of 0.1microns per meter planed or about 5 atomic layers. If the corrosion rate can penetrate faster than material is removed corrosion could be a factor for the abrasive rate will be enhanced by degraded corroded metal ahead of the abrasive wear. If it was Myth Busters I would call it plausible, but no where near confirmed.

Proof's in the pudding. All things being equal does a corrosion resistant steel wear slower? Intriguing. If there was a significant market for hand plane blades as there is for router bits someone would have found out