I'll also have a stab at 2), though I'm guessing somewhat here - happy to be set straight!
The only way you can have the same drag at 2 differing speeds is if they're either side of the minimum drag point, recall a L/D curve is some sort of U shape with: On the left high drag dominated by induced drag courtesy of excessive AOA. On the right high drag dominated by parasite drag due to excessive speed. The L/D curve is the result of combining the parasite drag curve, and the induced drag curve. Somewhere in the middle there's a low point where the combination hits a minimum.
given that, and what we already decided about lift in the climb being slightly reduced: you're going to move the induced drag curve a bit to the left (the wing is compelled to generate less lift at any given speed - effectively you have a lighter aircraft). that will move the min l/d left, and closer to the .67M figure.
So, I believe that transitioning from level flight to climb will favour the lower speed from a drag point of view. I have no idea of the magnitude of the change, or if it's significant. I would also expect it would only really figure at high altitude, as at any lower levels, the speed at which the low point occurs (best glide effectively) will be well to the left of where I'd expect anyone to be operating.
Does that seem reasonable?