After much deliberation on this one, microscopic checks revealed the cell structure to be unapologetically Racomitrium.
At first I thoughti t was one of the upright ones of the canescens agg., specifically ericoides. It was, ultimately, the Racomitrium cell drawings in Watson that allowed me to get at this one. Otherwise I was getting nowhere fast.
After a review on Google I'm now fairly convinced it's lanuginosum... see this one especially: Link
From the BBS field guide: "Confusion is only likely when you come across poorly grown plants, which may resemble the R. canescens aggregate (p. 540), but R. lanuginosum always has toothed margins to the hair point"
From University of British Columbia (link above), "The leaves are a linear-lanceolate shape. The presence of a broadly decurrent, hyaline awn with strongly dentate margins makes recognition of this species relatively straightforward." - you think? Now I know, those dentate margins seem to seal the deal. lanuginosum it is,
Racomitrium lanuginosum, Woolly Fringe-moss