From the DevNote, it sounds as if the IIsi polls the sense lines for monitor type, and likely the PRAM for B/W or grayscale/color bit depth, in determining how much of Bank A needs to be buffered for Video Memory.

Assumptions/Ramifications

If - Apple went to the trouble of tweaking the IIci ROM to limit Bank A to 1MB in the IIsi's Memory Mapping

Then - that limitation should disappear upon substitution of a ROM with a less limited memory mapping scheme.

If - hacking the IIsi's soldered in memory allotment in Bank A entails giving up the use of the Mobo's Vampire Video

Given - the IIsi's I/O expansion limitations imposed by the single PDS slot/PDS Adapter Or single slot NuBus Adapter

Then - Apple likely assumed that no IIsi user would bother to hack the IIsi's soldered in memory allotment Bank A

If - hacking the IIsi's soldered in memory allotment in Bank A does not affect the buffering of the first MB of a hacked Bank A

Given - the IIsi's Memory Map Limitation of 1MB for for Bank A

Then- that limitation should disappear upon substitution of a ROM with a less limited memory mapping scheme.

Assuming - a Hackintosh was a practical option at that point, the IIsi would be immediately dismissed as a viable candidate

WAG - No PROBLEM!!!!!!!!!!!! }