Teo Lachev takes us through visual calculations in DAX:
Suppose you need a measure that calculates the difference between the product categories in the order they were sorted in the visual. Implementing this as a regular DAX measure is a challenge. Yet, if we had a way to work with the cells in the visual, we can easily find a way to get this to work. Ideally, this would work similar in Excel, but DAX doesn’t know a think about cell references. However, visual calculations do.
As always, Teo gives us a view of the good, the bad, and the ugly with this feature.