Homozygous lethal is a possibility for any dominant type morph until proven differently. Homozygous lethal doesn’t necessarily mean anything bad about the heterozygous form just that you probably don’t want to breed them together.
Without a proven homozygous spider it would have been just as much a rumor to say that spider is dominant for years as to say it's homozygous lethal. It could turn out to be either. It would be very very hard to prove a homozygous lethal morph if the homozygous eggs never hatched. Even if a morph turns out to be dominant it's a matter of opinion how many babies it takes to prove that.
The BHB evidence that Pinstripe is dominant has been accepted for some time (2 years?). If NERD is getting close to that number with their potential homozygous spider and shares those numbers it will answer the legitimate question on spiders in most everyone’s mind. Even just hearing 2 clutches 2nd hand gets spider leaning more toward the dominant side for me than it has for years but without more info on the number of hatchlings or perhaps more hatchlings if it's low I certainly wouldn't consider it an answered question yet now 20 some years after the founding spider was imported.
Oh, and for what it's worth I might have started people considering the possibility of spider being homozygous lethal in an old post on kingsnake. I think Kevin started people considering the possibility that it's dominant on his web page. I don't really care either way I just want to know the answer already. It is what it is and don't think considering either possibility is less responsible than the other.