to cove or not to cove, that is the question

According to Exterion Media, whose job it is to sell on-bus advertising to anyone that will buy it, 86% of people can recall a bus advert they’ve seen (and I'm assuming they're referring to an advert on a bus, rather than an advert for a bus!).

Example of a route-branded cove mhd recently did for First
A figure of 86% is some claim towards the effectiveness of the medium. My own experience, mainly on Stagecoach Gold between Gloucester and Cheltenham, is somewhat different - especially where internal coves are concerned.

Not only do I not remember the ads (which isn't the bus company's fault) I struggle to see them in the first place (which, in a way, is the company's fault).

Assuming you are seated, 50% of the coves are out of view (that will be the ones directly above your head), leaving the remaining 50% on the other side of the bus. Unfortunately they are at such an acute angle you can't see them even properly if you wanted to. So if I can't see them in the first place, there's not much chance of me being able to remember them!

I've always found it a little strange why branded services like Stagecoach Gold allow external messaging in the first place. Obviously there is a financial gain but this has to be weighted against a diluting of the service's brand in the long term - especially when there is no control over the type of adverts that appear.

Showing ads for budget dog food on a premium service is hardly a match made in brand heaven is it?