Unless i am missing something, i can currently add only individuals to a team. In a cross-functional or matrix organization, it means that i will be doing a lot of manual additions, one person at a time. Instead, it will be much easier, and much more reflective of the groups-interacting-with-group picture you had delineated in your product announcement, If i can add a team to a new team.
It will save a lot of manual additions, and not only in the first time. If i later make changes to a team, these changes will be automatically reflected in all teams that include them ;-)
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