hello .... newbie here.
Came across this older thread and thought to throw in 2 cents worth.
In most cases ... at least around here ... you'll see the cable feeds strung along the Telco on outside poles. Bottom line .... that installer is full of BS.
Not trying to ruffle any feathers .... rather a couple of points for clarification.
AC lines have magnetic fields emanating from them which cause electromagnetic interference ( EMI ) for voice , data , video ..... which is why you shouldn't run them together in close proximity along the same path .... and the reason why you are supposed to go 90 degrees when crossing AC lines.
This is also one of the main reason why the separation from the pole to the building.
Telco ( POT ) line voltages are in the neighborhood of 48 volts DC ( ideally ) .... ring voltages are AC not DC . They range from about 45 - 90 VAC - 20 hz with 75 VAC being average. the reason for the AC ring voltage was to energize the the transformer windings for the bell ringer in older phones.
This is a moot point since it shouldn't affect the install.
As was said here already .... sounds like the installer was a lazy hack..... no surprise.