The Miller effect for grounded emitter is not beta times Cce, it is (Av+1) one plus voltage gain base to collector. This gain is approx RL(h+Re) where h=Ic/26mV. h=1/gm of the device. Therefore the miller capactance seen at the input of the grounded emitter circuit is Cm=(Cce)(RL/h+1), with no emitter resistance in circuit. The cacode circuit bandwidth is much improved due to the abcense of this effect. The Miller effect on input impedance dramatically reduces the operating BW with input sources that have signifiacnt output impedance.