Re your last sentence: try boarding a LNWR service early. If you are right l must have completely imagined standing on platform 11 on Saturday morning for 10 mins waiting for the doors of the 1146 to Crewe to be opened....
There can be good reasons for this (eg train brought in as empty coaching stock and crew working in service not yet arrived). Annoying as it might be there isn’t really cause for complaint as long as the train leaves on time and doors are opened within a reasonable time to allow boarding.