Personal situation of Russell aside, maybe the issue with the long pause between the albums might be a mix of other life commitments, such as work, or simply the inability to churn out on short notice quality material. Not everyone is able to lock himself in a cabin, count 1, 2, 3 go and write an album's worth of material that lives up to a band's name. Maybe they really need all that time to present a nice album full of good songs and not 3-4 great songs and a pile of meh songs written because the deadline is approaching.