Does everyone pull all the fuses underhood each time they change the tune like the broad year model instructions say. Is it really necessary?

 

Only necessary if you are error prone and, just for example, forget to turn off your air conditioning after driving the car for a while .

Had that happen once and the current draw when I turned the key (which started the air) caused the tuner to apparently hiccup...wound up having to go back to stock and then reload from there.

If you just make sure e'thing is turned off you should be ok.