Planned Hours is something we know we should be doing, but because each graphics project is it’s own beast, using Planned Hours has been hit or miss, and frankly, usually miss. So often it's just a wild guess or is taken off a separate spreadsheet of "averages" we update once in a blue moon.
Also, some have found Planned Hours sorta pointless when Workfront provides no way to keep assignees from going over-hours (hard limit). I think some just plug in a number to avoid odd issues when having tasks with zero planned hours, and only do it as they go.
It certainly isn't a metric we currently measure performance against!
So yes please thank you, your particular idea might provide insight.
