As a long time DYI WordPress user and (unofficial) tester I've often found Jetpack a bit more troublesome than it's worth. I've never really like the way it handles comment subscriptions and overall it tends to slow the responsiveness of a WordPress powered site. Of course, that's my personal experience on 3 different websites, mileage may vary and all that. But for comment subscriptions I've stayed with the "Subscribe to Comments Reloaded" which has never failed me (using Bluehost as a web host) and offers real management capabilities (admin).

Anyway, glad Dreamhost cooperated and reverted their "tweaks".