(Realizing this is somewhat of an old thread; maybe still pertinent though...)
I'm not a fan of recurves in general. But I've found out an oval diamond kitchen 'steel' is perfect for quickly resetting an edge and apexing on them. I use a 10" EZE-Lap oval diamond rod (~ 600 grit or so), which has pretty crisp edges to each side of the oval profile. I put the knife into a clamp or vise, with the blade pointing UP and the edge facing me. Then I place the tip of the rod alongside the edge at the heel of the blade, rotating the rod so the oval's narrow edge is flush to the blade's ricasso where it meets the blade's edge. I then push the rod away from me and UP along the length of the cutting edge, rotating the rod so it's oval center works the major portion of the recurve as it moves up the edge toward the tip. The length of the oval diamond rod, and the diamond abrasive, make it very fast-working in resetting an edge. I also lubricate diamond surface with some mineral oil to 'smooth' the work and keep the diamond cutting cleanly without clogging.
For lighter touchups on such edges, I've also used stones with one edge radiused (maybe 1/8" radius or so, not very wide), as suggested earlier by HeavyHanded & Jason B. That works well for maintenance, after the fact.