Again, what a bad judgement risk. I think its just mechanical grandstanding, i.e. "dune buggying". The motor heads have won the day. The mechanical abilities of the Rover seem to count more than the science, at this point. Those dark rocks are reachable from the rim at two points along the crater.

Squyres view of things is again an over simplification, quote:

"They are going partially into the crater now, to
reach and study some rock layers that were deposited long before the thin layer
they found in the crater they originally landed in ("That was the last page of Mars
history -- the waters dried up and blew away -- and we want to read earlier pages", Squyres
said."

Not so. Those rocks of Eagle crater are not the last chapter of deposition. There were perhaps hundreds of feet of sedimentary rock deposited above the rocks of Eagle crater that have since eroded away in the billions of years since deposition. This is evidenced by the residual deposits of berries, the lack of crater ejecta, and layered deposits in other, higher parts of Meridiana. Deposits near the bottom of the Valles Marineris have been determined to be Magnesium Sulfates also. Are these the last chapter as well?