So, in reality sportsmobile probably did not install either of the fuses I am referring two. Both of those should be placed close to the battery and I believe that the cross connect that they are referring two is a single sourced power line.
I see the the statement in their instructions, so I understand the confusion, but their wiring diagrams don't support that statement. Actually we would have to look it up in the ABYC guidelines. Might be worth a call to Blue Sea to have them explain. In either case installing it with out the fuses would put comparable to other Sportsmobiles with the Blue Sea installed. I don't expect that RIVA says you need to do this in their electrical code.
I don't believe if you had fuses in those positions that it would have prevented the flair up, the fuses would not have blown in time.
I have a V10 (battery in engine compartment) so this is what I did
-greg