> But, I'm pretty sure that the way the code works is that the initial
> disk label is reported up to sysinst to make a disklabel.  The
> disklabel needs to know the disk's capacity and it currently asks for
> a geometry.

So I guess you ignored the lines that say:

                d_link->sc_capacity =
                    (d_link->sc_params.wdp_capacity[1] << 16) |
                    d_link->sc_params.wdp_capacity[0];

which specifically get the drive's idea of its capacity in sectors.

Actually, I think this is all pretty much irrelevant.  The first and
second stage boot blocks should simply ask the BIOS for its current
geometry and use that to convert the block addresses to CHS values.  I
don't see why anything else in NetBSD should care.