With study, the sheets are for the most part self-explanatory. Though not at first glance, and no books or other references for "terminology" required. Best examples are the Carbine of the Month sheets in your newsletters.
I try to send data for guns I haven't touched, swapped parts one, etc, i.e. buy barrelled receiver from CMP, send datasheet, then have fun with it.
Are spot reports of mixmaster assemblies important? Guess some are, some not. For the price of a stamp, I let them figure it out.
FWIW, one of my to be reported sheets will extend the current High/Low serial number ranges observed for SG, at least as published early this year. All my other mixmasters can make no such claim to fame, but reported upon transfer into civilian hands they are as received.