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Using wedges to partition a very large disk (> 2TB)

The following is a transcript rather than a step-by-step set of instructions.

Partitions are chosen to be at a 4096-byte boundary and the filesystem fragement size is set to 4096 bytes too. An increasing amount of modern disks have 4096-byte sectors.

backup 1# grep ld1 /var/run/dmesg.boot
ld1 at aac0 unit 1: RAID 5
ld1: 4656 GB, 607896 cyl, 255 head, 63 sec, 512 bytes/sect x 9765857280 sectors
backup 2# gpt show ld1
       start        size  index  contents
           0  9765857280
backup 3# gpt create ld1
backup 4# gpt show ld1
       start        size  index  contents
           0           1         PMBR
           1           1         Pri GPT header
           2          32         Pri GPT table
          34  9765857213
  9765857247          32         Sec GPT table
  9765857279           1         Sec GPT header
backup 5# gpt add -t ufs -b 64 ld1
Partition added, use:
        dkctl rld1d addwedge dk<N> 64 9765857183 <type>
to create a wedge for it
backup 6# dkctl ld1d addwedge dk0 64 9765857183 ufs
backup 7# dkctl dk0 getwedgeinfo
dk0 at ld1: dk0
dk0: 9765857183 blocks at 64, type: ufs
backup 8# gpt show ld1
       start        size  index  contents
           0           1         PMBR
           1           1         Pri GPT header
           2          32         Pri GPT table
          34          30
          64  9765857183      1  GPT part - NetBSD UFS/UFS2
  9765857247          32         Sec GPT table
  9765857279           1         Sec GPT header
backup 9# newfs -O2 -I -b 32768 -f 4096 /dev/rdk0
/dev/rdk0: 4768485.0MB (9765857180 sectors) block size 32768, fragment size 4096
        using 25778 cylinder groups of 184.98MB, 11839 blks, 22976 inodes.
super-block backups (for fsck_ffs -b #) at:
160, 379008, 757856, 1136704, 1515552, 1894400, 2273248, 2652096, 3030944, 3409792, 3788640, 4167488, 4546336, 4925184, 5304032,
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