Captain reported local control position in tower issuing route clearances along with control instructions resulted in frequency overload and distraction while executing a precision approach in poor weather conditions. Controller stated this is facility's normal procedure.

Narrative

Safety concern while conducting ILS during at-mins IMC conditions at PHX. While cleared for ILS Runway 26; the Tower frequency was clogged up due to the Tower Controller's excessive transmissions. He was transmitting full re-route clearances to aircraft on Tower frequency. Normally this might not be an issue if the airport wasn't so busy; arrival rates were low and it was VMC. However; this night the weather was at mins; thunderstorms in the area and the probability of a go-around was high. To simultaneous broadcast on both Clearance Delivery and Tower frequencies is completely unsafe. It's very distracting to have a full re-route clearance broadcasted on Tower frequencies; while aircraft are conducting high workload; low visibility/low ceiling instrument approaches. If this is normal practice; which the Controller said; it was when queried on the taxi post landing. I find this to be unacceptable; especially with all the recent close calls seen on national news. Stop the simultaneous broadcasting on tower frequency during busy times. If the excuse is the lack of ATC manning; fix it. And here's an idea. If there is a last minute re-route that needs to be communicated; send it via CPDLC or utilize clearance delivery's reserved frequency.