as an alternative to a blocking diode, what about installing a crowbar diode across the power leads? .... Rashly assuming a proper fuse has been installed
Fuse? You mean we need a fuse?
Crowbar would eliminate the voltage drop but too large a fuse (over the rated current of the crowbar diode) could cause the crowbar to fail open, cooking the innards anyway. Everything is a compromise, and from the performance of our prototypes at low battery voltages (less than 11Vdc) it was decided that the .5V drop across the Schotky diode we have decided to try will have a negligible impact on performance.
We would have preferred to eliminate reverse voltage protection all together (a can of worms indeed) but as it only takes a millisecond mistake to let the magic smoke out, we might be replacing a lot of units under warranty that were ok other than installation error.
As far as a strobe/sos generator, it should be fairly trivial to design if one does not already exist as an IC. Problem would be where to put it (see comments on board density above) and how to trigger it. It might however, make another kind of neat project as a stand alone device wired into the supply side circuit? If properly sized, it could be used on existing anchor/tri-light circuits or any other resistive load.
Hmmm.. add that one to the list of future Franken-Projects for the community to kick around.