Looking at whether using Optimizely A/B testing would work with gas.
"Because Optimizely runs first and creates _gaq, it's very important for any custom implementation of GA to make sure it checks for the existence of _gaq before it runs, and if _gaq exists (because Optimizely created it and added a custom variable), make sure to include that value when the custom implementation runs."
Does this in the GAS src have that effect?:
window['_gaq'] = window['_gaq'] || [];
var _prev_gas = window['_gas'] || [];
Links