@wizard:
From a biologist's standpoint, yes it is a variation of line-breeding. However, there are enough other dog lines interjected along the way that it should not be a problem. The other bloodlines will swamp the Mischief Maker's contribution.
It would be a pity if the other bloodlines ''swamped'' the contribution of Lazer. He was a very nice dog and produced some nice dogs as well, with very little health issues. I love what has been produced by this sire, Cool Jazz, another very nice dog. Lazer pictured below:
The sire and dam are from half-sibling breeding…. not a big deal if the health is good, which I'd suspect it to be. As with Pat, I'd be far more concerned with any future hip issues, as is it is back on both sides, along the pedigree vertically too.
If you can't financially end up doing his hips anytime, just be wary that it is behind him, so don't completely ignore that fact.