I think you’re giving BA far too much credit over and above what’s really going on which is it’s cheaper not to put candidates in the sim, that’s all that matters to BA post Walsh and especially Cruz.
I’ve already stated that the process has been watered down recently by all this “suitable for long haul” nonsense. In the (not so) old days part and parcel of the BA sim assessment was looking at you with regard to your ability to pass any conversion including onto a Long Haul type if required so if you passed the sim the possibility of Long Haul was a given if you had the requisite hours. Any question mark and you failed, nowadays any question mark and you’re waved in onto the A320 Fleet seeing as no other bugger will take it.