Oh TOM! You made me laugh out loud!
Thank you so much, I really needed that!
Simple explanation really.
Way back in the early days of dial-up connections, I had two lines installed, one for the computer and one for telephone conversations.
With DSL the phone-only line was superfluous, but it would cost a small fortune to have Verizon come and change the DSL connection to it. It was much, much, much cheaper to have the filter installed on the computer line and do away with the -87 line. Got rid of quite a few thousand $$ a month that way.
Damn, Tom, I'm still grinnin'
HB