Repeatedly clicking on the radio button will toggle the radio theme styling
.md-radio-focused .md-radio-ripple .md-ripple-foreground
The reason is that given a focused radio button:
Mouse down will call _onInputBlur and remove md-radio-focused
Mouse up will call _onInputFocus and add md-radio-focused
One proposed solution could be to check if the _onInputBlur event's target came from within the radio input label and if so, ignore it.