The issue is Konstatinova has the potential to mess up very very badly to the point she might not make it to the free skate. Gubanova might be inconsistent but she still never bombed that badly.
Even at JGP Dresden which was the worst of her international showings this season, her SP score was 59.00. So what is this about not making it to the free skate? It's not like she has been scoring 40 something at all her SP's this year.