Sure, most umpires are nice people. Many are not. We solved those potential catastrophes in my association. All high school varsity games are assigned by a computer program that chooses the umpires based on coaching preference lists. Since we meet 13 times a season, as our state charter reads, for serious discussion of the rules of baseball, we hand those assignments out at the meetings.
Umpires get two week s work one week in advance.
On our assignment sheet the first umpire printed is the plate umpire. The positions cannot be switched except in an emergency or with the permission of the assignor. The umpires may be too busy or too lazy to worry about training. Here are some possible solutions, so that when the assignments come out, everyone will know where he goes at each game. They will insure that before each member of the two-man crew climbs out of his car, each will already know which one is going to pull on the tools of ignorance.