A somewhat interesting aspect is the assembly by hand and the POKEs from DATA statements (as you would do on most other micro computer systems). Notably, BBC BASIC featured a built-in assembler, so you could directly interleave 6502 assembler code with BASIC statements. – Was this some kind of obfuscation, or did the built-in capabilities of BBC BASIC fail to come to the notice of an otherwise well-versed kid? Or was this an intricacy of the Sideways RAM, which couldn't be reached this way?