Pilotchute,
I have some experience in this area. Professionalism is an attitude. It is NOT a measure of technical/manipulative skill.
You can have a candidate that has an absolutely fantastic and professional attitude to the job, but that means nothing if they can't fly for ****. Particularly if you give the candidate training input (which is permissible, as that in itself is a means of assessing trainability) and they don't show an improvement in their manipulative skills afterwards.
Professionalism is a state of mind and attitude.
Technical proficiency is a completely different matter.
You can also experience candidates that are great pole men/women, but have a **** attitude to the job.
If they were one and the same, airlines wouldn't do a sim AND interview as separate components requiring the candidate to pass BOTH components prior to being made an offer of employment.