It is tempting to call the resulting seesawing struggle between rival segments a mid-mac Alpin crisis, an equivalent of the mid-Stewart crisis of the second half of the sixteenth century. There were, however, three vital differences: the Stewart crisis through real enough, saw only once a rival claimant to the throne for although it may have been a dispute about royal power it was not about sovereignty itself, as this may have been. The Stewart succession, whatever the faults of the family, did not falter and it itself provoked instability. Nor was the mac Alpin crisis neatly contained within a fifty-year period for, despite the stabilizing effects of the long reign of Malcolm II, it resurfaced in the 10340s and was put to rest only with the death of Macbeth and his stepson Lulach in 1057-8.

Friction between rival segments had for centuries spotted the history of both Irish and Pictish kingship, for such was almost a built-in fault of the system of tanistry. The recurrent crisis which lasted for almost exactly a century after the death of Indulf in 962 was of a more serious dimension: the period might well be thought of as the wars of the Scottish succession. It was also a civil war: the long themselves', as the Annals of Ulster put it, which resulted in the death of Kenneth III, son of Dubh. It is difficult to be sure of what provoked this intermittent civil war: part of the explanation must lie in the fact that the successive killing of Dubh in 966 and Culen in 971 produced not two rival royal segments but three. The position of a mac Alpin tánaise (literally, 'the expected one') became suddenly far more insecure.