Using Optimizely I can create one or more experiments in a same project, but there is no guarantees that they will not executed simultaneously. For instance, if i'll create 2 experiments for a particular URL with Traffic Allocation for 100% visitors - all of them will receive both experiments. This isn't good, as experience given by first experiment will be combined with second one; they may conflict and potentially affect final numbers.

Official documentation tells that you can use custom JavaScript to setup experiments in the way that only one of them in a group will be activated for a visitor:

<https://help.optimizely.com/hc/en-us/articles/200040205-Mutually-exclusive-experiments>

I'm ok with JavaScript, but unfortunately, it requires to have predefined list of exclusive experiments in code and copy-paste that script into each of experiments. Also, that technique doesn't takes into account Targeting rules, as having all those experiments in a list doesn't guarantees that all of them will be activated.

I'm looking for JavaScript, which can be placed above/below Optimizely snippet. That code should know which of experiments are matching for current page view and activate only one of those experiments.

**Update: 12 July 2014**
Optimizely updated their code, so it seems like now everything becomes even more complicated. Anyway after long reverse-engineering and debugging session, it looks like problem might be solved in case if we can randomize order of existing experiments before testing them for traffic allocation rules (after today's changes - unsegmented audience).