Need Another Seven Astronauts

Back in '86, that was the punchline to a rather morose joke.

I don't think NASA has learned anything.

CAPE CANAVERAL, Florida (AP) -- The space station's two American astronauts went out on a riskier-than-usual spacewalk Wednesday to fix one of two equipment failures that have crippled their power system and threatened to stall construction.
[...]
Whitson and Tani performed virtually the entire job in the darkness of night, pausing during the daytime swings around Earth when 160 volts of electricity would course through the cables. As an added precaution, the spacewalkers were advised not to point any nonessential lights at the solar wing in question to prevent power generation.

Because the [200 pound] motor serves as the structural backbone for the solar wing, the spacewalkers had to make sure the wing didn't come off and fly away.

Since when did NASA engineers switch from redundant systems to multi-purpose systems?