A lot of people who work in the field feel differently about the usefulness of human explorers Barry as should be obvious to anyone who really follows the work on extremophiles. It is human intensive not robot intensive.

I have two reasons for sending humans to Mars. The search for evidence of past or present life and establishing a second home for humanity. The fact that you ignore obvious evidence of both interests is in line with your usual look at only the data that suits you approach. I think finding life on Mars would be wonderful and a huge driver for exploration of Mars both robotic and human.

Your contamination mantra is just silly over a time line more than 10 years. 10 years is plenty of time for basic robotic follow-ups to any signs of life to clearly determine the genesis issue and slay the biohazard dragon. Humans on Mars can do the things they do best while easily controlling robot explorers in areas needing a more sterile approach without the long delay Earth based remote controllers would suffer. Landing on Mars will not instantly contaminate the whole planet. These same issues are dealt with routinely in Earth based research.

Your silly chant of the same claims over and over despite obvious contradictory evidence does nothing more than confirm the opinion of most here of the sluggishness of your thought processes.

Regards,
Mark