We know Buemi wasn't hired for his looks so it's not inconceivable that the guys got talent. 
It looked like he was about to kill off Alguersauri's STR career following Monaco...but then Algersauri, his back up against it, make a decent enough recovery in Montreal and then Valencia and then Silverstone. That's three races on the trot that Buemi has seen his target worm his way back into the competitive mix.
For all we know Alguersauri is stupidly quick and, so, Buemi is a man to watch.
Red Bull are known to discard drivers at a drop of a hat:
Liuzzi, Klein, Bernoldi, Doornbos, Freisacher, Speed, Bourdais, Armermuller, Zaugg, Hartley...the racing circuits of the planet are littered with young Red Bull Academy prospects who've become cannon fodder.
We'll see.