Thank Curley again! manually editing grub.cfg is amateur as it is
auto-generated. but my stanza is simple, it's easy to add it if removed.
if it were Windows, it would be much easier
i examine syslog, among many lines probing each partition for OS, i
can't find how i specify installation target for grub during
installation. installer show 3 options, /dev/sda, /dev/sdb and
/dev/sdc, plus manually entering path. surely i didn't trouble myself by
manually entering. if i choose correctly, it strengthen my belief that
legacy mbr is poorly maintained (they focus on mainstream gpt)
