What made the last two possible

Worth recording because it is the transferable part.

A sweep inside the probe instead of a rebuild per guess. One refusal code from a five-argument call says which step failed and nothing else. Finding out by editing a constant costs a package build, an install and a launch - about five minutes, with a healthy console needed for each. 085-videobuf varies one argument per call and reports each code, so the whole table comes out of one run:

baseline        0x80290015
format=0        0x80290003     <- the argument is read, and the baseline value is fine
aspect=1        0x80290008     <- so is this one
720p            0x80290015

Two codes moving is what proves the attribute is parsed and that our values pass - which is what made it possible to stop varying the attribute and go and vary the allocation instead. Neither half would have been enough alone. (D251, D252)

A second source. Three findings recorded as facts about the console turned out to be facts about this program, and in every case a second source existed and had not been consulted: ~/oracle/uroot/eboot.bin, a title that launches. Every question put to it this session was answered in one command.