We have purchased Tableau Desktop 10.2 licenses, which are licensed per “Authorized User”. May one user perform any number of installations of the software on any number of devices?

No, this is not allowed in the case of Tableau Desktop. Contrary to the usual practice, this user-based software may only be installed once on the primary device of the authorized user. Additionally, the user may perform another installation on a second device which belongs to him.

Source: EULA_Tableau Software_Tableau Desktop and Server_Feb 2017_as is 2017-04-04