You said: "it was a waste of effort" ... "No benefit whatsoever" ... "more confusing for shooters" ... "more work for me" -
The first three claims are untrue. More work for you is true. Running a GP match is a huge amount of work. I don't mind a little extra work. If you want to go less, why don't you skip the lane signs as well. It would save you some more work. Less to "confuse" the shooters. NOT.
"Next some will want us to give them all of the target distances!"
Slippery slope? It's interesting how logical fallacies are presented so often in these arguments. To me, it's an indication the presenter is short on valid arguments.
"If it is a big deal for anyone they can shoot in a different division..." - No, they can't. And what does Division have to do with signs?
I'm guessing that you think signs are ALL about ranging. It's not. Telling the high scorer at a big GP match they lost because they shot the wrong target order. That's not fun. I'd gladly put in the extra work up front, rather than deal with target order instructions, and protests, and any resentment from competitors. Shoot the targets in their numbered order. Confusing? - NOT.
Are you concerned about the ranging aspect of providing signs? True, it will make bracketing easier for shooters. But they will still need to learn the skill to do it effectively. More shooters will probably take up the skill. Outside of AAFTA, range finding by means other than focusing is the norm for all HFT games. The match director can do a little bit of work to encourage Hunter shooters to learn a new skill that is directly related to the HFT game. I'm willing to put in a little extra effort.
If you really don't like signs, don't use them. I already put the work in, so I decided to share and make my solution available to others.