Thanks guys for all the tips! I may have to leave it then as I hadn't taken into account any springback more heat would cause.
Sadly, the stave has one beautifully straight limb which didn't need touching, then dead in the middle of the handle area it developed 45 degrees of twist, 5 inches of deflex, and a long s-bend that took forever to heat out! I'd love to remove the deflex as 5 inches BEFORE it sees any tillering is just nasty but if removing it means meeting the twist and lateral bends again I might just go a bit crazy!