This makes sense with what Toro Rosso is ostensibly supposed to represent, however I believe the feeling is that Red Bull wants to part with Toro Rosso at its earliest convenience… I’m not sure if this fits in with the seeming lack of interest in dumping both Buemi and Alguersuari. I think you’re completely right in that they don’t appear to be anything special and its time for the next lot of Red Bull youngsters.
I’m sure people will point out Buemi lead in Canada and Alguersuari has had some good runs, if that’s enough then they should have no problem slotting into another team or they should move up to the main team if they’re considered good enough. If they aren’t good enough to do either of those things then they shouldn’t be treading water at Toro Rosso when Ricciardo and Vergne are waiting in the wings.