Multivariate or A/B testing is very cool and useful. Today’s solutions are very flexible and allows you to test several pieces of marketing (ads, lading pages, etc) in real time without the need of being an expert. You have tools for any particular need, free solutions like Google Content Experiments; paid solutions for a low price like Convert, Optimizely, Unbounce and VWO; and paid solutions for bigger budgets like Adobe Test & Target, Sitespect and Autonomy optimost among others.
Even though this kind of solutions are great and useful it is important to know what are they useful and are not useful for. A/B testing and Multivariate solutions are useful to test a “Short list” of changes or optimisations after you already know them. What they can’t do is let you know what are those changes you have to test. Let’s put it this way, if someone tells you “what do you prefer, that I give you a punch in your eye or in your stomach?” You will probably chose the eye or the stomach depending on what bother you less. However that doesn’t mean that you like to be beaten.
Before running A/B testing or a multivariate testing I highly recommend you to run surveys to let your users chose the short list to be tested (without they knowing that). If you just show them just a few combinations that you have in mind, you could be leaving aside some other possibilities that can drive you in a better manner to your business result.
A/B testing or multivariate testing are a behavioural source of information. Behavioural information can just answer you “WHAT” the user is doing but not “WHY”. It is important to know what kind of information source can answer different questions so you can go there and get the answer. The “WHYs” can just be answered by Attitudinal information sources like surveys.
You have also a full range of surveys solutions both Free like Survey Monkey and Google Forms; and paid like Zoomerang. So, if you wanted to know what they are thinking just go and ask them, no excuses.