If I understood this post correctly, it looks like there might have been 2 different Kickstart 3.1 40.70 versions:
THE FIRST is Kickstart 3.1 40.70 ROMs for A4000T released in 1994:
These A4000T Kickstart 3.1 40.70 ROMs have scsi.device replaced with NCR scsi.device and workbench.library has been removed and added to Workbench 3.1 A4000T floppy to make room for NCR scsi.device code. NCR scsi.device is needed for A4000T onBoard SCSI.
THE SECOND is Kickstart 3.1 40.70 ROMs for A4000T or A4000D produced somewhere in 1995 and 1996:
These A4000T Kickstart 3.1 40.70 ROMs are reported to have workbench.library and normal scsi.device, just like in previous 40.68, however Commodore/Escom/whatever noticed it was a little picky on harddisk+CD-drive combinations and was reported to cause problems with some harddrives and accelerators so after producing some they gave up and switched back to 40.68 to avoid those problems.
Assuming because of the bankrupt the developers responsible of Kickstart coding stopped working in a situation where they could soon solved those issues. So we may never find out if there is just a little typo in 3.1 40.70 code that could be corrected by some skilled hobbyist. Or who can say if using 40.70 in A4000D really just got a bad reputation mainly because of bad design in some old harddisks, CD-drives or accelerators or the well known bugs A4000D Buster version 7/9 or even, because A4000T has Buster 11 and it had they decided to continue using 40.70 there. Ofcourse no software or hardware is 100% free of design errors, so what I'm saying is that there must be bugs in all Kickstart versions but there are no proper documentation about how likely it is that all these problems were caused just because of A4000D with 40.70.
It is also a shame they didn't move to use bigger capacity PROMs, so removing something like workbench.library to fit in new code would not be necessary. As programmers know when something new is added to the code something old may break and after adding something new the code would have needed full testing if every old feature works.
Anyway I think the Amigakit product code: AMIROM007 with the following chips...
MX J9648
391657-01
V3.1 (V40.70)
(C) AMIGA 1995
42747JY9
MX J9648
391658-01
V3.1 (V40.70)
(C) AMIGA 1995
42706JY9
...could be one of those second versions. At least the fact that they are manufactured 1996 on week 48 supports this theory. Or why would they produce any Kickstart 3.1 ROMs for A4000T at that date, since all A4000T were indeed shipped with Kickstart 3.1 40.70 anyway and while in the edge of the bankrupt I don't believe that they would dare to produce these chips just for spares just for A4000T models that were quite rare in the first place.
For A4000D IDE normal scsi.device is needed and for A4000T NCR scsi.device is needed and both are used by system with the same name scsi.device. So how could any Kickstart work in both A4000T and A4000D models when only one scsi.device can exist in one Kickstart?
Sources:
http://amigakit.leamancomputing.com/catalog/product_info.php?products_id=476 http://www.gregdonner.org/workbench/wb_31.htmlhttp://wiki.classicamiga.com/Kickstart_Roms_Explainedhttp://www.amiga.org/forums/showthread.php?p=302371http://eab.abime.net/showthread.php?p=260038