I think it's a great idea. It would be particularly useful if any form of life activity was discovered on Mars, and it might be many years, if ever, before enough study was done of the planet to completely rule this out.

I am a lot more worried about human colonies infesting a fragile ecosystem with our bugs than the other way around, and teleoperation of sterile probes and machinery would be a great way to do large-scale operations without worry. A few humans landing would be okay, if extreme care was taken to prevent contamination.

Such a technique would be even more useful at places like Venus, or Jovian moons deep in the radiation belts (might need optical links.)