As much gnashing of teeth as there has been over the whole coupler thing with ST, you'd think they'd relent and just do it. It's become too much of a distraction. I contend for every penny they save by rolling their own, they spend a nickel on administrative, support and marketing to defend their decision, and that's not considering the costs incurred in multiple retools to get one that works.
I'll put my tin hat on and posit that whatever is driving this priority, it's gotta be personal. Gotta be. They do everything else so well, so why not the couplers?