out of bounds pass

[Nevadaref]

Originally Posted by just another ref

I am in the group that incorrectly does it. Why is it proper in this situation to chop the time in when the ball becomes dead?

Because the rule, 5-9-4, states that the clock shall be restarted when the ball is legally touched by a player on the court. That player can be either inbounds or out-of-bounds. The clock should start on that touching and then stop as soon as the official blows the whistle for the violation. Never starting it isn't proper according to the rule.