Resolve Outlook Cache mode On Issue

We were wondering, if there is an easy way to resolve the outlook cache mode issue. Currently our estimation is that 10-15% of our users have this turned off and they are getting errors after upgrading to 2015 Add-in(since 2015 quietly made is mandatory for it to be turned on we believe). Our outlook team is not very encouraging to make this update via group policy, since it hits all the users and it could create performance issue for other users. So, we were wondering if we can target specific users to turn this on, may be if they is a registry setting etc.

Any help is appreciated.