Why so few 15C/11C application and program books?

[Dave Britten]

I've noticed that the 11C and 15C, despite being heaped with (not undue) praise, have relatively few application books and program libraries for them. Is this because the target demographic was more naturally drawn to the 41C, where there was no shortage of modules, books, program libraries, and peripherals, and where the alpha display made programming easier? That's my hunch, but then the 34C (essentially the 15C's predecessor) had a few application books published by HP, and the later Pioneers also had quite a few despite coexisting with the 48.