Re: Excellent work!
"We need a mission that sods the accuracy and fancy calculations and just salvo-fires a ton of cheap experiment en-masse in the hope that just one works."
A) Litter bug.
"And if the Mars Rovers had been closer? Maybe one could have helped repair the other."
B) So at the start of your comment you're advocating throwing primitive disposa-probes at Mars in the vague hope that something might stick, and by the end you were proposing that Mars Rovers be qualified mechanics for each other? Probably best leaving the science to the scientists; unlike you they landed Philae on a Comet with a margin of error less than a degree beyond the main asteroid belt.