I'm still green on this shorty business, but 28" sounds like a lot for a 54" all wood bow (typically you take draw and double it for minimum bow length for most woods if bending in the handle). I think here in Texas commercially traded bows are supposed to be given poundages at 28", whether or not they actually draw to 28. Maybe that is the case with these? Otherwise i'd be highly cautious about such a bow. Tillering further out would depend on the wood type, profile, etc.
I'm sure others with more expertise will post soon. Probly need more info, pics, etc to be real help.