The notice template param select list when working on a notice template still inserts a <<>> syntax replacement variable.. we should start using [% %] instead to encourage the adoption of TT more widely.
OK.. this isn't as trivial as it looks as we do special cases for 'borrower-attribute:CODE' replacements and possibly others.. as such we can't just change <<>> into [%%].
*** Bug 33822 has been marked as a duplicate of this bug. ***
Can we just deprecate the attribute syntax entirely.. it appears to be entirely undocumented.
No, we can't just remove it.. it's exposed in the side picker and as such is likely in use.