What’s your source for phone calls weigh more? Because i heard from someone who helped design the capitol hill constituent services IT that they are exactly the same.

It's possible different legislatures or even individual legislators have different preferences, but I believe this is what I've heard in MA politics

My source is experience in MA legislation: AFAIK they tally the same (not a formula), AND, from MA staffers, forms that make e-mailing quick and easy are often not read deeply (still do them!). Phone calls take longer and are often lower volume than emails and therefore stick out more.