Feedback on 12V water heater element as solar diversion load

StirCrazy,
It has definitely crossed my mind from the start of this little project. I admit that I have been hoping that the 6 gallons of water as a heat sink will never be able to reach the blow off valve setpoint with this diversion load. Assuming I am leaving the propane water heater burner off. But if the diversion load gets disconnected, then I have all my panels directly wired to the batteries with no control. Which scenario is worse?

I also don't know why my sig won't show up? The box is checked.