Surecast I find is on such a small duration to actually be of any real use though - as you never know when you'll be interrupted, it effectively a wasted ability slot (not to mention the chance of being interrupted when casting a healing spell is actually very small now due to tweaks SE has made since the Beta, unless you happen to move while casting). Swiftcast on the other hand... it's value simply cannot be understated. Used with Raise (or Resurrection) and bam, instant raise. It's probably the most useful cross-class ability in the game really.

So it's well worth taking THM to level 26 simply for this ability alone (Blizzard II can also be useful when soloing, but it's not really needed when you're in a party as CNJ/WHM).