Case-sensitivity of key/id-like data items

[rowlesmr]

pdCIF has some id-like data names (_pd_block.id, _pd_phase.id, _pd_diffractogram.id) which are supposed to have unique values associated with them.

The description of _pd_block.id says:

Blank spaces may also not be used. Capitalization may be used within the ID code but should not be considered significant - searches for data-set ID names should be case-insensitive.

which describes Code, yet the content type is Text.

Other discussions (here, and here) suggest Word, and Text as appropriate choices for the content type.

Code is a case-insensitive sequence of CIF2 characters containing no ASCII whitespace.
Word is a case-sensitive sequence of CIF2 characters containing no ASCII whitespace.
Text is a case-sensitive sequence of CIF2 characters.

Is there a single content type that can be chosen for all (pdCIF) key/id-like data items?