[1] This grouping was proposed by Hans Kuhn as an alternative to the older view of a Gotho-Nordic versus West Germanic division.

[2] The Northwest Germanic theory challenges these proposals, since it is strongly tied to runic inscriptions dated from AD 200 onwards.

The date by which such a grouping must have dissolved—in that innovations ceased to be shared—is also contentious, though it seems unlikely to have persisted after 500 AD, by which time the Anglo-Saxons had migrated to England and the Elbe Germanic tribes had settled in Southern Germany.

This means that direct comparisons between Gothic and the other Germanic languages are not necessarily good evidence for subgroupings, since the distance in time must also be taken into account.

(Such areal contacts would have been quite strong among the early Germanic languages, given their close geographic position over a long period of time.)