One could argue that they have them already... called caddies. Can't see it making them any faster by giving them range finders - electronic or human, it's all the same. They're still going to hum and haw about things, because while we mortals play for pro-shop vouchers, they're playing for a six figure minimum prize!
I don't think it would make a difference. The course guides that are compiled for the caddies are so extensive that they already cover pretty much every dip, marker or object, so they know how far they are away from the pin at any point on any hole anyway.
I don't know if you managed to catch the Masters on the BBC on the Saturday (I think) where they talked you through the pro course notes and the guidance they also issue re: pin positions. It's pretty detailed and specific, noting how many feet a pin is located from the inner and left edges of each green.
Pros at that level don't really judge distance in the way us mere mortals do; it's a scientific calculation for them which their caddy starts.
Incidentally, slightly off-topic but kind of related, I will try and get a link to a good YouTube video of Luke Donald a few years back playing the a par 3 tee shot several times, each time with a different club in his bag. Was pretty impressive how he knew exactly how to control the distance from his 56 wedge right through to the 3 wood (the 3 wood was the only one that went through the green, incidentally).
I think would take some of the reliance of the yardage book and it's quicker looking at a range finder than opening a book. The range finder would give the exact figure so no need to calculate extra distances I.e. it's 150 yards from that tree and we're 8 yards from the tree.
Having that basic figure will allow player and caddie to then factor in other factors when making their shot selection. So there's still a need for a caddie and it simply speeds that first calculation. Wouldn't be a dramatic time saving but it could only help and given the fact that they are already used extensively in practice roundsI can't see any reason why they shouldn't be allowed during the round.
It might make it a nadge quicker if the caddies could just call the number but then the pro would want to know the distances to other targets etc and so chances are it'll make no difference in the big scheme of things. Not likely to happen anytime soon
No difference at all IMHO. The caddies give the players yardages almost instantly, what takes the time is convincing the player he as the right club and talking about the wind. If NBC gave the players exact yardages before they got to their ball, they'd still take forever t hit the damn thing. I call it paralysis by analysis