I think you are setting up HH as a bit of a straw man for debunking. Your focus on HH as the sole measure of fabric quality is not how the real world operates. In addition, many of your claims are either wrong or misleading.
> The testing is done under ideal conditions with new materials that have not been
> pre-saturated, creased, folded, stretched, walked on, or otherwise subjected to
> what would be considered "normal use" before measurement.
Reality is that even here at BPL we have had tests run on fabrics both in the new state and in the 'used' state. Such testing showed that spinnaker fabric was great when new, but leaked a bit at the creases after a while. It also showed that while Cuban was great when new, the lighter grades tended to get pinholes at the creases after a while. We KNOW about this.
I am sure most serious tent and tarp manufacturers are aware of these things and do their own testing and assessment as well.
> The test only reveals the pressure threshold at which the material allows water to
> seep through. It does not consider the volume of water that is allowed through
> after that threshold is reached
True, and false.
As an extreme example, EPIC fabric is great when new and at low pressure, but we KNOW that once it gets dirty or once you exceed the threshold it leaks like a sieve. We KNOW these things.
I think what is happening here is that the vendors have to simplify things so they can make the specs for a tent fit into a finite space for the 'average' customer. HH is used as one obvious and useful parameter in a spec list, but not the only one. Not wishing to be rude to the world, but I suspect that most customers (especially novices) wouldn't know what HH really means anyhow, and further detail would be wasted on them.
> This measurement offer no real indication of the durability of the floor material itself
So? It is a measure of pressure, not of fabric durability. To suggest otherwise seems rather silly to me. Once again, would the average tent buyer know what a Martindale test is? Or the difference between nylon 6,6 and polyester? Or ...
> I simply think that HH is realistically a very poor measure of the quality of a material.
I don't think anyone else has ever suggested that HH is a measure of fabric quality. It is however a useful measure of the waterproofness of a COATING. We use other parameters to assess overall fabric quality. Come to think of it, what do YOU mean by fabric quality anyhow? You have not even defined it. And if you haven't defined it in measurable terms, thern you cannot measure it.
I understand what you are trying to say, but I suggest that the problem is that you may have misunderstood what everyone else is talking about. We don't talk much about tensile strength or tear strength as, for the most part, the fabrics used have more than enough strength. I don't know of anyone else who has ever suggested that HH is the sole measure of fabric quality, but it is a useful spec for the coating.