I use Bristol quite a lot and find the herding of SLF very irritating.
Industry-wide, it does seem that the root cause of ridiculous baggage scenarios and poor boarding timings is indeed the terror of handling agents at the lowest level - terror of being disciplined if they use their discretion or cut things too fine. A little more emphasis on common sense and less use of the stick would work wonders in giving passengers a better experience. But is there any indication that anyone on high is bothered?