Hi Sara,
When I run phenix v1.6 via the GUI, starting a fresh refinement session from the main window (I do TLS+isotropic ADP refinement and 5 macrocycles, otherwise everything default), I saw these non-default refinement settings in the run, which I did not specify myself, but the program:
this is specific to "tls+individual_adp" strategy only. TLS+isotropic ADP refinement protocol is highly optimized by re-refinement of several hundreds structures from PDB to find the optimal refinement parameters. These parameters are coded in phenix.refine and currently cannot be changed. In future versions of PHENIX this will be changes to a user will be able to overwrite these automatically picked values. If you use "optimize_wxu=True" then the value for wxu_scale is adjusted to achieve the best Rfree and Rfree-Rwork. Please let me know if you have any questions! Pavel.