When we shoot the classifier at our club we load our mags up to the max to save time. I see no harm in carrying extra mags on your belt during the classifier.
Recently went to the NM IDPA Championship in Farmington, NM-they didn't do Chrono. It is my understanding that if any competitor has doubts about whether another competitor's ammo is making PF then they can request the MD chrono the ammo. So it's on an "as needed" basis at some matches. Other matches may use a Chrono stage tto check the PF of all competitor's ammo-for example, the Arizona State IDPA Championship in Phoenix.
Just use Dillon's number of 1.260. Work up a dummy load using this OAL. Barrel check it-if it drops in freely, turns freely, and drops out freely then the OAL is OK. Crimp would normally be around .469-470
Sounds like you are from Farmington and the only world class shooter there shooting CDP is Glen Shelby who recently destroyed the courses of fire at the NM State IDPA Championship there on the 25th. Welcome to the Forum.
It appears this is a 1-man business run out of home. Owner, Mark Thomas, attends a lot of matches all over the country as well as gun shows. He has a good reputation-give him some more time.
I am not sure the CR Speed mag pouches and the DAA pouches are legal in IDPA. If they are I would use the DAA pouches. If not, you can select from Blade Tech, CompTac, or Ready Tactical all of whom make good products.
In a club match I really wouldn't mind-they have to start somewhere and if Dad (or someone else) is coaching them I have no problem with that. I would hazard a guess that you are not going to see teenagers or younger at an Area match or higher. Some thought needs to be given to the "legal" problem brought up earlier if a death or injury happens while a youth is ROing. Does the national organization have a lawyer on staff or on retainer?