Some inconsistencies are apparent within the TEI, which does not expound a precise set of principles for consistency. For
example:
<name reg='Volange, de'>de Volanges</name>
but not
<w reg='though'>tho</w>
(<w> marks a word, and "reg" indicates regularization). In the second case it is necessary to say
<w><orig reg='though'>tho</orig></w>
which is inconsistent with the first example.
When tags are used to mark not only structural or logical objects in a text, but also to describe their properties, considerable verbosity can result. For example, if it is also necessary to indicate that the word is emphasized (<emph>), it is necessary to say
<w><emph><orig reg='though'>tho</orig></emph></w>
Note that in this example, there are six different permutations of the three tags <w>, <emph>, and <orig> allowed by the DTD to mark the same fact. Potentially all of them could appear in the same document using the TEI DTDs. This seriously weakens the structural model of the text, since at a certain level virtually anything can contain anything, thus creating problems for validation, search, etc.