Figured this might be a useful snippet of perl for other folks.  When I rebuild my system last Nov, I wiped the drive with the following:
my $a = 0;
while ($a < 312581808) {
  my $b = 60000;
  if (($a + 60000) >= 312581808) { $b = ($a % 60000) - 1; }
  print "\n$a: ";
  `hdparm --trim-sector-ranges $a:$b --please-destroy-my-drive /dev/sdh`;
  $a = $a + 60000;
}
To use, mount your SSD on another system (or use a system rescue CD or LiveCD with a new enough version of hdparm) and replace “312581808” with your actual number of sectors (check with fdisk -l or similar) and /dev/sdh with your actual drive.
The tricky parts were:
(1) Figuring out the syntax, although I suspect that it’s better documented now.
(2) Figuring out the 60,000 sector limit (actually 64k/65,536? Dunno. 60,000 exactly worked.)  I’m not sure if this is an hdparm limit or an Intel X25M limit.