The B737 FCTM allows touchdown with full crab up to max crosswind limits. It also goes on to suggest it is the more preferable technique on very slippery runways but its not recommended to use this technique on a dry runway at max crosswind (which incidentally is generally more in the FCTM than in operator's limitations).
It may well have been your trainers preferred crosswind technique but labelling them as clueless is a bit harsh.