easy has had exactley the same problem getting Airbus guys (including some VERY experienced ones) through the check on the 737-300.
Fly-by-wire is just so fundementaly different from a conventional aircraft that
1) You can hardly blame the guys for losing their basic skills when they haven't had to use them for years
2) It's ridiculous recruiting Airbus pilots to fly Airbus aircraft on the basis of whether they can fly a geriatric Bac 1-11 (put 'em in a Tiger Moth-That's what I say!!)
Best way to assess an Airbus pilot? In an Airbus sim!!!