There isn't an official "delegate" command. But you can add the other person as an approver and remove yourself as an approver. That has a similar effect. We do that quite often on our team for the approvals of certain kinds of work items.
Vinay Kumar AV selected this answer as the correct answer
Yeah... I thought of the same. Wanted to know if we do have a supported feature for delegate. If this is there, the delegation can be explicitly captured in history.
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