By that logic, if you train your WC students well, they should be able to hit you at will without you being able to pak sao or bil sao, since the WC punches are not telegraphic and even trained fighters cannot evade or block them.
So learning all the WC techniques for blocking attacks from out of contact range is a waste of time, as WC punches can never be seen, countered or evaded.
Doesn't add up, does it?
Good technical boxers NEVER use an all or nothing approach. And BTW, Jack Dempsey advocated the moving forward behind the punch approach you say is unique to Wing Chun. You should read his book, that way you'd know a little about boxing, it's on Stickgrapplers' MA archive site.
You've watched "Choke" and a few UFC's and instructionals, and you feel you're equipped to lecture people with years of BJJ and/or wrestling about grappling. You watch boxing on TV, and feel you know as much or more about it than Dale, who's been doing it for decades. That's your right, I guess, but don't get affronted if someone calls you on your prejudices, judgements made from a state of ignorance of the subject.
Much of boxing tactics, especially defense, are more efficient and economical, and safer, than some WC techniques. Do some real research sometime, at worst you might learn something.
If ANYONE in boxing, kickboxing or MMA thought that WC gave them significant advantages, they'd employ it. These people are not fools; inflexible thinking will not get you anywhere in any martial sport. There's lots of money to be made. If anyone though this stuff would give them an edge, they'd pick it up in a heartbeat.
My si-hing's school in Queensland entered fighters in an NHB show in Brisbane on the weekend. Twelve fights, nine wins, two gold and two silver medals. WC influenced kickboxing
and BJJ..