[searealist]

Lighter roasts channel more than dark roasts and also make more of a mess coming out of a grinder (more static).

[noSyncCloud]

It says in the linked article that darker roasts have less internal moisture content (obviously, they've been roasted longer) and therefore produce more static/clumping.

[searealist]

It does not say dark roasts have more static, and in the real world light roasts are much harder to brew.