Hi Simon,
The problem with S.1932/DOC45 of Alexius I is that divides into (at least) three different subtypes, as listed in my table. DOC45a is the full weight half-tet, while 45b & 45c-d are lighter and perhaps later issues.
On the other hand the 203 examples from Thessalonica quoted by Lianta are not distinguished by subtype – all we have is a gross figure for "DOC45" as a whole.
So what were Lianta’s Thessalonican coins? Were they all DOC45a? Quite possibly, but we don’t really know.
Ross G.