p.s. does this yellow book have any use with respect to obtaining reasonably priced medical care for routine treatment at hospitals/outpatient clinics in the Tambon/Amphur where it is obtained

No.

The only foreigners that get "extra" entitlements are those with (or who previously had) a work permit and who pay social fund contributions or foreigners who are married to government workers.

again i don't believe that is entirely accurate.

Fair enough. Do you think what I posted was incorrect; do you think I missed something out, or both?

no i don't think you said anything incorrect at all. i only stated in a previous reply that i had personally met and seen a couple of foreigners here in C.M. that did not previously have work permits and to the best of my knowledge were not married to government employees, receive low-cost outpatient healthcare at a small hospital/clinic here near my home in C.M. by way of presenting a copy of their yellow book. i was at the clinic a couple of times and personally witnessed it. i am not 100% sure about one of them but the other volunteered that his wife owned a shop for many years so i know she is not a government employee.

I guess there are two possibilities. The first is that the health care was cheap anyway. The second is that they managed to get added into the 30 baht system some time ago and they have managed to stay in the system somehow.