Marc gives a good reason why Telco and Cable can't be attached to a service mast. Another reason that I believe this is in the code is that if you have Telco and Cable drops right under a power drop nasty things can happen, such as bridles on telco and cable getting pulled off, or worse, if the triplex starts to sag, and abraid against the coax, you could end up with a shield at 120VAC.
BTW, we just relocated a cable drop a couple days ago, all it took was a cordless drill and an eye-bolt
JMHO,
-Will
