When they manned the ISTAR they were sat right next to the boss, so they were learning. We only had 2 L2's, both of which were trusted but one was shot early in the tour and sent back, never to be seen until we got back. His replacement (when we finally got one) the boss didnt trust to do even arty tgt.
We used to do cree training early in the tour, but i got bounced around different OP's and PB's, the boss and the FAC never got out of the ops room except for company ops (not stuck in there by choice) and the second Ack was sent off to a PB and then shot. Yes we were a cursed FST, the only 2 casualties in my battery were both ours.
Needless to say, crew training didnt happen much for the fact that the crew were rarely together with any spare time. We did get plenty of downtime, but not at the same time in the same location. I think another reason for FSI's becoming common is that the MAC wants an arty FST bod in every PB or FOB that he commands.