It may seem like I am merely trolling for viewer hits here. However, the logic behind this counter-intuitive statement is based on the political factors that shape people's opinion on climate change. (E.g. Rather depressingly, support for the theory of man-made climate change increases when the weather is hotter.)
The other important thing to realise is that methane is a much more powerful greenhouse gas than CO2 over the short-term. Yet, it's potency fades the further we look into the future, whereas CO2 remains in the atmosphere for millennia.
Here's the take-home:
Tying everything together, a move to natural gas might conceivably benefit the long-term climate in two ways. First, there is simply a direct elimination of carbon emissions due to the switching away from coal. This obviously presumes that fugitive methane leakages are not high enough to offset those gains. However, even that runs parallel to a second point which has been the focus of this post: Methane emissions in the present will drive up temperatures (but not over the long-term) in a way that likely encourages political action and hopefully helps to establish a coherent climate policy.
To conclude, I’d rather see global temperatures follow a concave path over the coming decades, than a convex one. In less technical terms: Accepting an acceleration in near-term temperatures in order to secure the political will necessary to enact long-term climate policy, seems an acceptable trade-off from my perspective.