As an aside, the scroll boundary being too close to the edge of the screen is maybe the only real criticism I have of Xanadu II, otherwise my favorite action RPG on the system.
That's because Xanadu (I'm assuming), and a lot of other games on systems (mainly Japanese PCs / ZX Spectrum...) with no scrolling hardware used the "push scrolling" method. It's probably not mentioned on that page, because push-scrolling largely sucks shit.
(Well, to visualize what push scrolling is, think of how Moto-Roader pushes the trailing car back into the centre of the screen, except that push scrolling does this with the
leading character, with tile-based updates rather than smooth scrolling.)