Can't argue that it doesn't fill a "niche" but it just seems redundant to me and the differences (to most people, other than knife people like us) are so minor (except for the blade steel used in the Tenacious which is made up for in the much lower price point) as to be almost entirely meaningless to most people.
But, different strokes for different folks. If it floats your boat, buy it. Using a shotgun approach by tossing out as many different models that people "might" buy (and cutting them out quick when they don't) seems to be Spyderco's marketing strategy, especially for it's more popular models like the Native and Endura/Delica lines.
It's just not another Spyderco that I see any reason to buy, given all the others that I already own.