Create a data element from an existing element is very convenient, especially when I need to make changes to my initial query, this way I only have to modify it in one element and all others are updated accordingly.
I was curious to verify if it could be also convenient for performance/execution costs, so I created two identical dashboards with one table and two single-value viz.
In the first dashboard all the elements use SQL query as source, while in the second one the two viz use the table as Data Element source.
Refreshing the dashboards data, I can see in my data-warehouse logs that for the first dashboard three queries are executed, while for the second one only one is executed 
Has anyone else looked into this topic or noticed anything interesting?