I\'m using the Javascript API for Google Analytics Content Experiments and it seems like you have two choices:
when running many simultaneously experiments the problem is that if you have visitors from one experiment that interact with elements of another experiment running on your site then it is difficult to account for these interactive effects. This will skew your data and lead to some faulty conclusions.if you’re absolutely confident in how to analyze multiple concurrent experiments, it’s okay be safe and run one experiment at a time.