Runners on 2nd & 3rd my catchers will throw down to 2nd to get a runner taking a big lead. We hope the runner on 3rd tries something cute. Delayed steals will only rarely work against us. However, if they are viable for a team they are certainly an effective tool. If you can, I say use them to abuse them!
Last weekend my DD's team hosted some pretty good travel teams to prepare for the start of their Fall season. Saw a few things common in travel ball that just will not fly at the upper levels. Saw a very fast runner on 1st try to take 3rd when a slapper laid down a bunt. The slapper was thrown out by at least a step and the runner going to 3rd was out by several steps.
As the game gets faster some things just will not work. Other things will only then start to work. You have to coach to the appropriate level of your talent and the competition. How many times have you seen a HS team trying to execute like a top tier college team? It is just plain silly. However, there are some things in HS that you can get away with that are extremely effective. In 10U I have seen teams that can bunt small ball another team to death putting 4-5 runs on the board without hitting the ball out of the infield. Use what works for you. Remember that if it is stupid and it works it isn't stupid!
Riseball, you bring up a good point. I've seen high school teams go for the out at 2B when there is a runner on first and the ball is bunted. I think it's generally fool's gold to attempt to get the out at 2B with a good runner at 1B. Get the sure out at 1B, then explode of toward 3B.