> Define "third".  If you mean "third in the usual list of eight
> partitions each disk has", then you can indeed; that's the one with a c
> at the end of the name.
> If you mean "third in order from the beginning of the disk", that
> depends on the disk label.

I don't much mind letters instead of numbers to label partitions (though
if BSD had as many partitions as I'm used to having (31), letters just
wouldn't do...), but:

> I suppose it's a matter of taste.  I rather like having disk numbers
> (the number after "sd") assigned from zero upwards as the kernel scans
> the available controllers and target IDs.  This is occasionally useful;

It takes exactly once occurrance of a drive in the middle of the chain
not responding at boot time for this feature to get OLD awfully fast.
Fortunately, having the higher numbered disk mounted in the wrong place
didn't actually cause any damage before I shut the system down...