TiteBond and other wood glues work best with smoother mating surfaces. You must remember that TiteBond III and other top-of-the-line wood glues are designed for modern cabinetry and the smooth surfaces and tight, void-free joinery associated with it. TB has NO void filling properties. Urac/epoxies are able to fill voids and will tolerate mating surfaces with slight architecture (i.e. toothing). Some even require this in order to grip and bond properly.
Here's some literature copied from the manufactures of TiteBond (
www.titebond.com) and Urac 185 (
www.nelsonpaint.com).
Regarding TiteBond:
"When working with woods that are high in tannic acid or are considered oily, wiping the joints with acetone before gluing them up ensures a good bond. Acetone clears the contaminants from the wood's pores on the bonding surface and dries quickly without leaving any residue. A good bonding surface can also be achieved by sanding or planing the wood just before gluing the joints."
Regarding Urac 185:
"Urac 185 is a modified urea formaldehyde liquid adhesive formulated to give craze resistant glue a line up to 0.02" thick. It may be used for gluing wooden structures where a thin glue line cannot be obtained because of inadequate pressure or irregularly contacting surfaces. Urac 185 is an ideal "gap filling" adhesive."
Hope that helps