Extending capability of Multivariate or A/B testing to custom component

I would like to know how to extend the capability of Multivariate testing to the custom components say Carousel.

I went through the documnetation at: http://dev.day.com/docs/en/cq/5-5/wcm/multivariate_testing.html and found that the OOTB Multivariate testing component exposes one or more image banners and maintains report on:

> Number of Views/visits by users

> Number of clicks - Click Through Rate.

I would like to understand whether this is applicable only for banners or can be extended to other components without having to do much of code change? Kindly advice.