This is a safety concern due to improper combustion and carbon monoxide entering the structure.

I would not shut off the water heater at the gas valve because you would have to relight the pilot later and leaving it on at a reduced temperature will help prevent rust in the combustion chamber and it probably won't use more gas than the minimum charge anyway. 

Use low flow high efficiency large drop shower heads rated at 1.5 gpm.Look for 1.50 gpm @ 80 psi, 5.7 L/min @ 550 kPa maximum water usageAlso, consider upgrading to condensing water heaters or seal combustion ones when the time comes.  98% efficient means $0.98 of each dollar goes to heating water, compare to 86% efficient water heaters. 

I went though the "Resolution Trust Corporation Bust" and I heard "This time will be different" for the DOT Com bust. 

After the dot com bust artificially low rates were vital to creating the housing bubble, which was a credit bubble (mal investment.)  

He didn't measure or even look at the very expensive single-walled stainless-steel flue I installed, nor did he check for the mandatory 3 inches of clearance from combustibles (ok, maybe he just eye-balled it).

but I never had to really define that or use that as leverage to cure any problem, there was a drug usuage and prohibited items stored section, like no more than 50 rounds of any caliber amunition, gasolene or combustible fluids, acids...etc, not usually found or stored upon a residential premises. .

In a couple of years when we do the outside of the building, we'll apply 2" of rigid foam on all three faces and 2" of rock wool board on the fourth (it's a zero property line and non-combustable exterior insulation and cladding must be used).

"Volvo Cars, the premium car maker, has announced that every Volvo it launches from 2019 will have an electric motor, marking the historic end of cars that only have an internal combustion engine (ICE)..."

With inventions like printing presses, telegraphs, and internal combustion engines maintaining the rule of law over distance became alot easier, and states (countries, not TN or AL) are now able to ensure the veracity of their paper currency.