You are already focused capped and use a wand without focus. A wand drops that has a ton of focus on it but it sits lower on your BiS list than the one you’re currently using. Most would be like ‘Mines Better’ and pass on the item. This is where having focus in the equation helps. If the wand with focus is higher on the BiS list when you include focus it may be better to use the focus wand and swap out one of your other focus items for one without. How can you tell which item to swap out? Check your Focus BiS Column . Now obviously you could weigh that up at the time the wand dropped but having something to reference is just so helpful, especially for players that are unsure on this sort of thing.
Also... adding focus into the DPS formula shouldn't affect the healing list as it should be using a different formula as the weight for SP:SC should be different anyway.
The formula I gave to work out a weight for focus was more for people to be aware of how to incorporate it.