After numerous unsuccessful attempts, and the use of several otherwise effective techniques, at removing the ridiculously large and tenacious burr my shun knife would produce I finally made it succumb.
I did what I really thought I should have done from the beginning but felt would not leave the best edge. I raised the burr at a very acute angle then, flipping the knife over I used exclusively into-the-edge strokes while raising the angle very slightly. Did this on 1K and 6K stones, then finished with a few passes on my fine Arkansas.
Not as sharp as I'd like but still sharper than blades of ordinary stainless. I'll do better next time. It's really only the last inch of the blade that gives the problem, but as a steak knife I need the sharp there.
Ah but I think what I really need is a new steak knife.