The Imaam during Qiraa't in Salaat switches to several different forms of Qiraa't.

Answer

Whilst the Salaat will be valid if the Imaam hops around in the Qiraa't like a rabbit, it is not permissible for him to hop around in this manner because it is quite manifest that he recites according to different Qiraa'ts in the same Jahri Salaat to impress the musallis and to flaunt his 'expertise'. In Sirri Namaaz he will not do so. His mode of hopping is therefore riya which is shirk-e-sagheer (little shirk). If he does so in the Sirri Salaat and in his own Nafl Salaat, then it will be permissible, but not when he leads the Jamaat in Jahri Salaat.