wiring pure and msw inverters together?

[inetdog]

Every time I see this kind of reference I cringe.
Shorted output to input; output is higher Voltage; inverter fries.

How about shorted output to ground. Anything is higher than ground. Output circuit fries (taking rest of inverter with it).....

[Cariboocoot]

How about shorted output to ground. Anything is higher than ground. Output circuit fries (taking rest of inverter with it).....

Nope.
Shorts can only occur within a circuit. Ground is not part of a battery circuit unless it is connected to it. Which is where the problem lies: negative input on inverters normally is connected to the safety ground. Tie one side of the AC out to ground and you've connected it to the input. Lack of isolation within the unit causes the problem. Components designed for 12 VDC in nominal really don't like 1/120th second of 10X their rated Voltage.

In fairness, not all MSW inverters suffer from this. They are not all alike inside. They don't all have the same input or output specs. Some of them can work this way.

These days it's just easier to go with sine wave and eliminate all the potential issues.