[heatmizr]

I have heard of this happening to varying degrees, but cannot fathom why/how this would be designed into the system. In what decision tree does the onboard computer decide to pull the plug on nearly all useable power?

Or are there two more clear cut scenarios here:
(1) those who get a "Limp mode" which allows you to get home or dealer fine, but engine will not provide maximum power. Considered normal vehicle function in reaction to certain problems.
(2) those who get the OP's more extreme experience whereby there is an issue above and beyond #1, not considered normal.

We've come a long way from the clogged catalytic converters choking your engine so badly that it can't maintain speed.