Great back and forth that I wish I had chimed in on earlier. Here's the official answer:
An install of PFO (doesn't have to be licensed...only installed) is only necessary if you want to run these Trimble Positions TerraSync tools
from the Trimble TerraSync toolbar in ArcMap - TerraSync Configuration Manager, TerraSync SSF Record Editor, TerraSync Data Dictionary Editor, TerraSync Data Transfer, and TerraSync Studio. There is no requirement to have PFO installed to perform check-outs and check-ins with the TerraSync workflow. That holds true for both Trimble Positions and Terra Office add-ins for ArcMap - both of which support TerraSync workflows and include the optional installer for these tools. Although it was our intent to distribute everything necessary to run these tools with the separate installer, it was too difficult to unwind the dependencies on the older coordinate system components that we no longer use or include in Trimble Positions and Terra Office.
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Matthew Morris
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