I have probably mentioned this before but Cornmarket started to offer advanced IAM drivers a discount with IAM Surety many years ago but then realised that LGV driver were so close to advanced drivers that they added a section to offer LGV drivers a discount
This is born out by advanced observers who found that LGV drivers going for the advanced needed very little advice in order to pass the advanced test
When I was observing I often went out with a LGV driver using the company lorry on a delivery run for 5 or 6 hours and for the first half I was giving advice then on the back half I left them to it then told them to put in for the test which every single one passed first time