Sharp-flowered Rush versus Jointed Rush

Having found a plant I thought was Jointed Rush I was keen to find Sharp-flowered to make sure I didn't have it mixed up. Happily on Sunday I ran across Acutiflorus in the Orchid Meadow in relative abundance and was able to snag a couple of samples for comparison. The two key points of ID panned out as expected - Jointed has blackish tepals and less flowers. Sharp-flowered is a light brown and has more flowers. In the examples I found Jointed is also only about half the height of Sharp-flowered, and happily grows along the sides of the path (and in the middle where not disturbed), and also in the "Mossy Barrens" - the old reservoir bed - is quite widespread. Sharp-flowered is carving out a living amongst the Tufted Hair-grass and Meadowsweet.Of course I have no idea how representative these samples are of the plants elsewhere. Here's a side-by-side:

Juncus acutiflorus vs. articulatus