Of course, it may be that she is right and he is wrong.
Why would you hope that he is right and she is wrong?
If he and GISS are right it means that in order to even have any measurable effect on global temperatures would require in practice an immense forced downsizing of industrialization and population/agriculture resulting in huge conflicts, rebellions, forced famines, wars, etc and with those actions cripple the advancement of civilization. If he's wrong, we've wasted unimaginable wealth, resources, and lives for nothing.
If she's right it means we can concentrate our efforts and resources more on the gradual adaptation necessary and having a pretty good model of the time curve and likely temperature rise boundaries to work with, thus saving immense wealth, resources, and lives and restricting freedom the least.
Didn't realize forced famines and wars were that popular on /.