To be honest, I think it's the genuine Cloud who's peeking through when Tifa asks if she's just getting ahead of herself again. The confidence of 'soldier' Cloud allows him to assure her that he loves her (True Cloud).
I am in agreement. Furthermore, Britt Baron, who voiced Tifa, stated during an interview with Square that a certain scene with Cloud was her favorite scene to record for Rebirth. According to her, Tifa tries to express her feelings for Cloud.