Right, I missed that. Furthermore, in Dead Mac Scrolls, page 147, he goes further than the 1990 book and says the MR824 is the preferred heavy duty replacement part if a GI854 part is failed shorted. I looked briefly at the datasheets and the 824 is definitely beefier, similar in reverse recovery speed, but has somewhat higher junction capacitance. But if Pina says no raster glitches have been observed using the MR824, maybe beefier is better...