Had a bard on EQ live wayyyy back in the day.
I can confirm the singing steel BP invigorate effect healed for 100 every 6 seconds. This let me "bard tank" from 45 to lower 50s
Here is quote from 2002 on the matter
https://everquest.allakhazam.com/db/...03522476784963
Healing %s had no effect on items in classic EQ
Edit: It was either 90hp heal or 100hp heal. I honestly can't remember which. 100% sure it was not 63hp heal.