Advanced Aggregation: Should I disable core's aggregation? I know that AdvAgg's bundler will, by default, disable core's grouping logic, but I'm unclear as to whether core's aggregation should be enabled or disabled (at admin/config/development/performance) for AdvAgg to be able to aggregate files in the first place. 

Basically, I can't tell if AdvAgg is actually aggregating things itself (and thus core should probably be disabled under admin/config/development/performance), or if AdvAgg is taking core's aggregated files and only handling the bundling aspect of aggregation, in which case core's aggregation would need to be enabled. I suspect the former is the case, but I can find no explicit information on this.

Can anyone tell me what the general best practice here is?
Should I disable core's aggregation?


No; AdvAgg uses the core aggregation setting as part of its own on/off switch. If core aggregation is disabled, AdvAgg aggregation is implicitly disabled.

In fact if you do disable it, you get this helpful error in the status report:



You can tell whether or not AdvAgg is producing your files from the path - it will contain /advagg_(css|js)/.