We've been asked why we only use fescue to overseed our lawns.  The biggest concern people have is that there is a preconceived notion that fescue is a much thicker, more unattractive blade than bluegrass is.  The truth is that newer varieties of Turf type fescue are hard to distinguish when held up to a blade of bluegrass.  K-31 Fescue is the type of fescue that presents a thicker blade.  Newer varieties are developed for their superior presentation in the lawn (See picture for differance in size from K-31 to turf type).  Fescue is also much more drought tolerant and disease tolerant than bluegrass.  That has never been more evident than this season when bluegrass stands nearly completely died out while fescue stands still struggled but held up much better.