Should Kubica be deemed capable of setting relatively competitive laptimes in his test in October, why would Ferrari decide to stick with Massa? Even if Kubica doesn’t have a potential world champion in him anymore, I doubt he’d perform worse than Felipe. Even if that would indeed be the case, what does Ferrari have to lose by hiring Kubica? Putting aside the possibility that Massa would dramatically improve next season, Ferrari would still lose out to any other team that has a similarly performing car but two scoring drivers (McLaren), but thanks to Alonso beat those that have considerably slower machinery (Mercedes). Considering that Massa is losing Ferrari second in the constructor’s championship but isn’t actually helping them remain third, hiring Kubica can only be profitable.
Of course, Alonso might not be a happy bunny should Kubica be as strong as he was prior to his accident. However, considering that Massa isn’t even quick enough to support a potential title challenge by Alonso, I fail to see how the negatives of a quick Kubica outweigh the positives.
If Kubica turns out to be able to set representative lap times I fail to see why Ferrari would want to keep Massa over him. It’s not as big of a gamble as it seems it is; he would either be as quick as Felipe or even slower – which wouldn’t really matter all that much for the constructor’s championship due to Alonso stellar performances – or he would be massively quicker than him.