A Scientist is Skeptic. This is not unusual. They follow their beliefs. Sometimes they live at skeptical camp, and when other they stay at denier camp. Interestingly, The Deniers tend to the name Skeptic. The Deniers call their opposite side as Alarmist. But the Alarmists claim they are real Skeptics. Both are skeptical. They are scientist.
Muller made his statement clearly and specifically about global warming. WUWT should not be nervous. However, Muller believes that the rate of global warming is now insignificant but it is true. Muller is no longer a Denier.
Not long ago, James Lovelock said that Gaia hypothesis has no scientific validity. The Deniers took it as a sign of victory.