I was under the impression that anything assigned via SPRINT will be turned into a .tra reference when --traify is used, while anything assigned via TEXT_SPRINT will remain embedded in the file.
However, when testing just now, I found that this is not the case. SPRINT strings behave as mentioned, but a TEXT_SPRINT string remains embedded in the file unless the string is used elsewhere as a .tra reference, in which case it is also changed to a .tra reference.
e.g.
OUTER_SPRINT x ~sprint~
OUTER_TEXT_SPRINT y ~text_sprint~
PRINT ~print~
Executing --traify on this code snippet assigns a .tra reference to the OUTER_SPRINT and PRINT lines, but not the OUTER_TEXT_SPRINT line.
OUTER_SPRINT x ~sprint~
OUTER_TEXT_SPRINT y ~sprint~
PRINT ~print~
OUTER_SPRINT x ~sprint~
OUTER_TEXT_SPRINT y ~print~
PRINT ~print~
Executing --traify on either of these two code snippets makes all three lines use .tra references.
I'm not sure if this is a bug or if I just don't understand the intended uses of SPRINT and TEXT_SPRINT.