Wondering why all those +health/5 sec items didn't seem to be working?

Blizzard has identified a bug preventing items that regenerate health over time from working in the intended way. This has been reported to the development team and will be fixed in the next patch!

The fact that items which periodically regenerate a certain amount of health are not currently doing so while in combat has been brought to the attention of our Quality Assurance and Development teams for further perusal; it was decided that this was not the intended functionality for this particular mechanic.

As for Troll's Blood Potion, as opposed to such items as the Stormpike Insignia, it is actually not intended to restore health while in combat; this is currently considered to be the correct functionality for the consumable in question.