Unfortunately the only answer to your problem [the idiots] is to lengthen the time they have to serve on the streets before any promotion.
At the present, even without direct entry from all sorts of police orientated jobs like selling ice cream later in life, the ACPO material can get off the streets after 2 years [and 6 months of that might be training] whereas if the minimum figure was instead 5 years they might have actually learned something about the survival of the fittest.
The downside of that is that the born and bred idiots would be there [carrying
your coat] into battle for that much longer!!!!
It isn't going to change any day soon..... its been like this for 200 years...!