Road Wheels & Road Wheel Recommendations?

I'm pretty sure it is the wheel flexing. The cage is very close to the spokes in the top gear and not helped by being a short cage. It's also probably in part down to my crap climbing techniques rocking the frame from side to side. I shall pay more attention next time I ride the bike although it's currently in hybernation.

Its just that (if I'm picturing this right), a 0.5mm movement near the cassette, would mean a 3 or 4mm movement at the rim. So you'd get horrible brake rub*. Yet if the wheel is simply being pulled up and down in the drop-out. You could get cage rub, without any side to side rim movement.

(I have cycled a couple km behind a guy with this much flex, on a mountain climb. You could see the brake caliper shuddering each pedal stroke. I was afterall behind him. So cant critisize too much)