I did a search and I think the issue is with the abillity getting added in a configurable too late for #hasability[] to get a proper tag count and is always returning a 0 or being added via configurable isn't setting the right tag for #hasability to include it in a count.
ShadowChemosh talks about this in a thread
here and suggests using hero.childlives[xxx] as the test criteria and also says #hasfeat[] has the same issue.
I'm not sure if this will fix your issue, but it's worth trying.