[C C Kent]

If the grandfather is an excellent representation of the breed and carries no congenital defect, the breeding is not too close at all. If not for line breeding the type and structure begins to fall apart. It depends on whether the breeder has the knowledge and experience to properly evaluate the common ancestry. In line breeding favorable traits are said to be "set" but unfavorable traits are as well. All in all there are fewer unknowns with proper line breeding than with straight outcross. I personally prefer that the common ancestor not be in the same generation on both sides. JMHO