... I have never tried tracking with the GPS, but will. I would agree, I think the difference, at least with my boat, is very subtle, minimal like you say. And as mentioned, I agree ... the boat manufacturers will hype anything. "Dramatically improves upwind performance" (per Tartan) is hardly the case for me. Nevertheless, again as you said, I'm certainly very happy to have the CB, but for many reasons other than going uphill, and mostly to tuck in close.

Here is a photo of the block I mounted on top of my CB. Before there was only a large pad eye, the line stopped there, so no purchase. The added purchase certainly does help, very easily up, in fact easily by hand, no winch. I was a bit concerned about two lengths of line fouling in the block, but so far, knock on wood, not problemo. My pennant is Sta-Set I think. The SS backing plate, tapped for fasteners to the block, was embedded inside the Board when we split it open, then filled with structural filler and glassed over.

Cheers, John