Please help me clarify overall focus. I have found snippets of information, but nothing to pull it all together.
I understand item focus. If you are wearing a specific level (max) focus and cast a spell higher than that, you still get the benefit of focus, just reduced for every level above the level of the focus.
I understand tribute focus. Basically, the same as item focus. Do they stack?
I think I understand potion focus. I say "I think" because I have seen comments where it is noted that a lower level potion still gives benefits to "higher" level spells (i.e. HoTs). Is this because having the buff automatically adds > 0% benefit which automatically is "rounded" to 1 additional tick? So, is it just as effective (and cost efficient) to carry the VII version rather than having the X version around? Someone asked the question in another thread about potion level VII still giving an extra HoT tick at 95. Do they stack? Alla's info included for reference:
Tonic of Regeneration Affinity VII
Effect: Regeneration Awareness VII
1: Increase Spell Duration by 5%
2: Limit: Max Level(80) (lose 5% per level over cap)
3: Limit: Spell Type (Beneficial only)
4: Limit: Effect (Complete Heal (with duration) excluded)
5: Limit: Effect (Invulnerability excluded)
6: Limit: Min Duration (24.00 sec)
7: Limit: Effect (Reaction Radius excluded)
8: Limit: Combat Skills Not Allowed
The big question is: Do all these effects stack? By running a potion and tribute while wearing the focus on items, do I get benefit from all? Is there a cap? Do I need to go to max tribute (X) and max potion (X) or can I get by with a lower level tribute or potion focus level? Presumably, this is the same for all focusable (is that a word) spells (DoTs, not just HoTs).