Slab breakoff: a causal mechanism or pure convenience?

The idea of lithosphere delamination has long been conceived as a mechanism to cause tectonic uplift, metamorphism and magmatism in active orogenic belts [1-3]. Since the publication of the two seminal papers by Davies and von Blanckenburg [4,5], the idea of slab breakoff has been more widely accepted over the last ∼20 years as the favored mechanism to cause collision zone magmatism and exhumation of subduction-zone metamorphosed rocks. These two papers showed the physical probability of slab-breakoff during continental collision and illustrated possible geological consequences using the Alpine geology as an example. Currently, slab-breakoff seems to have been axiomatically accepted as the causal mechanism in studies of continental collision-related magmatism. In this short paper, I do not intend to deny the probability of slab breakoff nor to object the possible geological consequences, but emphasize that caution must be exercised when invoking "slab-breakoff" as a causal mechanism without physical and geological justifications or if evidence clearly indicates otherwise or contradictory.