I could see HR/GE being somewhat feasible, but my biggest concern is that then HR would be deirectly responsible for performance management of all front end team members. I think aspects of the job like scheduling and owning myGuest seem reasonable. my concern is that it could turn into a situation where TMs don't trust HR because HR isn't impartial anymore and is having to coach them and initiate CCAs for performance based reasons and not just conduct. Granted, if the HR is a fair and consistent leader, then it may not be too big of an issue. The combination of these roles might just seem to blur the line between the role of HR and every other leader.
At least with HR/AP they are the direct supervisor of the least team members of any etl, and most matters involving other team members will be conduct based.