Scientists against indirect land use??

I'm not surprised Midwestern Senators are against including indirect land use in GHG emissions calculations for corn ethanol... but a consensus of scientists?

On March 2 one hundred of the nation’s top scientists, including preeminent members of the National Academy of Sciences, wrote a letter warning that it would be a mistake to enforce a new and highly uncertain category of carbon emissions — indirect or market-mediated effects — against only biofuels. The scientists wrote that all fuels have indirect carbon effects and that these effects are not well understood or readily quantifiable.

It's very clear that biofuels do indirectly change land use, it's just measuring the "how much?" that is problematic.