Elemental focus + support

Does using Elemental Focus support allow you to have the 16% damage from no ailment spells from the Elemental Focus node, or just the 10%?

The 16% is just elemental damage and has nothing to do with ailments. The ailment effects will not inteact with Ele focus since it prevents ailments. If you are using Ele Focus support and the ele focus node, you'll get 16% increased damage and 10% chance to avoid enemy ailments on you and that's it.

If you don't use the Ele Focus support and take the ele focus node, you'll still get +16% ele damage and a 10% chance to avoid enemy ailments, but any ignite you cause will also do 10% additional damage while the efects of chill/frozen/shock will be 10% greater.