Yeah a lot of fans think his writing hasn't been the same since Sam Loeb died...the quality hasn't been there since that happened that's for sure. It is very sad indeed.
I think Loeb's decline goes back further than his son's death. I don't disagree that Sam's death was a blow -- the earlier poster who said he lost "a part of his soul" is, I think, not unfair -- but I really think that the real turning point for Loeb was Archie Goodwin's death in 1998. Loeb lost a collaborator who was willing and able to push him, and his work after Goodwin (such as Dark Victory
, the Marvel "color" books, Superman/Batman
) has moments of brilliance, but those moments are like the needle in the proverbial haystack.
Also, and some may find this a heretical viewpoint, I think that Loeb and Sale reached their peak with A Superman for All Seasons
and they should have let their collaboration go because it's been diminishing returns since. (Though the zero issue of Captain America: White
showed some real promise, even if the series itself has been MIA for years.)