I am not sure anyone with enough 'clout' will read your post, though, it may be worth sending your feedback through responsetek
http://www.cableforum.co.uk/board/forumdisplay.php?f=81
as, messages via that do get seen.
Unfortunately though, the support guy was correct - NTL do not officially support routers and it is always best to connect direct when they are trying to 'tech' a problem. The support guy was just following his training, NTL's stance is that they will support the connection to the modem, anything other than that is down to you - and will often be scapegoated as a potential cause of the problem, even if logic dictates otherwise.