I managed to figure it out and I'll have the same problem as I had read. The monitor lower limit for horizontal sync is 30kHz so 15kHz 480i isn't possible. While it could take RGB from the PS2, it would only display when getting a 480p signal, as it's own menus and the majority of games are 480i it would be out of range.
I tested it in practice by telling my graphics card to fire out some 480i even if it was an RGBHV signal, out of range.
So... My idea of Guncons and Time Crisis on super shiny Sony Trinitron's dies. Oh well.
