It's been a bunch of versions back that I had occasion to use this tag. However, I just realized I have a similar tag that is working:<br>
<div style="text-align: center;font-size:150%;line-height:110%;">
That one I use as V0 to display the page number and title of hymns.
<br>OK, I give up. I just created a test song with both tags, and they both work:<br>
---[Verse:1]---<br>{s250}Test Line (250%){/s250}<br>{tt}Test Line (Title){/tt}
Lane