If you look at the graph pictured on the post, copied from the bitcoin wiki, it does not always "grow and grow", because it is in fact graphing the percentage of the total bitcoin days, not the absolute number. This is further described on the stackexchange post, and you'll note that my answer there explains that it has been flat over the last 3 months.
I agree that it is quite different from a velocity measure, simply because it was not intended to be a raw velocity measure. Bitcoin has some unusual features which require unusual metrics. This is just one that is being explored, as an alternative to raw transaction volume, as the posts explain.
Seems like it could be an Arabic script to me, which could be used in a language in the Middle East or various other places in Asia, Africa, China etc:
Then paste that into google translate, and choose "detect language" in the "translate from" box :)
But Arabic is tricky with how characters change appearance depending on their context. And I can't find that V-like character with a stroke at the top, second in from the right in the lower word that appears on either side of the door.
I agree that it is quite different from a velocity measure, simply because it was not intended to be a raw velocity measure. Bitcoin has some unusual features which require unusual metrics. This is just one that is being explored, as an alternative to raw transaction volume, as the posts explain.