Anything other than a cross of two homozygous, for the selected genetic markers, strains would be an H1 cross. As there are no documented homozygous strains, all strain crosses would be considered an H cross.
On a side note, genetic markers are the sites on the chromosome where traits are determined, so the terms marker and traits can be used interchangeably.
Same answer as the previous example, H1 rather than F1.
Gold Colombian x Sumatran Tuk Tuk would still be an H1.
I'm unclear on what your question is here. Can you rephrase it so I might better understand?
I can say that homozygosity in a gene line has it's advantages, in that every seed breeds completely true to it's parent, however, it also brings it's own inbreeding detriments as well as it can have detrimental genes locked into it with no heterozygous genes in it's offspring to allow for adaptability to changing environments.
Just because all known cannabis strains aren't homozygous doesn't mean they necessarily need to be. We have already overcome much of the need for homozygous strains in the commercial industry by making such wide use of clones.
As I eluded to above, there is absolutely room for slight, or even moderate, genetic variation within a population, if you have the resources to run a bunch of seeds, find a great clone and use it to share/produce your stock.
Another thing I'd like to point out, because I think it's being taken defensively, while I believe it is meant more out of respect and deference towards the wisdom and expertise of the cannabis grower/breeder.
**The scientific community has in effect stated that cannabis is a special plant, both in it's use and in the practice of breeding it. Past and current cannabis breeding has caused cannabis to not fit the old nomenclature regime, probably because it's versatility and usefulness! **
The scientific community is basically saying "You cannabis breeders have created this new thing that we want to assimilate into the old nomenclature system, but we need you to name it something that isn't already being used by the old nomenclature system". This is cause for celebration, not alarm. Scientists want to work with us as peers, that's a genuine honor being given to a community of people that have traditionally been outcasts of our greater society.