Jeff, that might be a question to back channel to Casey Carlson and Scott Hutton who I understand are Ron Harr's executors. Ron was kind enough to share quite a few drawings he made with me along with a good number of maps and photos, but nothing that I can recall on Tipton. With your knowledge that they did in fact load livestock at Tipton, the loop makes a lot of sense for turning stock trains in addition to the obvious wintertime use. One thing about turning the snow plow that seems odd is that the snow plow seems to have been typically kept at Austin and as Terry observed, the loop switches are facing point toward Baker rather than Austin. Maybe I am wrong about the typical location for the plow, but that is where it is shown in most photos when it is sitting out of service and that is where it was in 1916 when the railroad was snowed shut for several days.
So far as I know noting has been mentioned on this board about Ron Harr's passing. For those who did not know him, he spent the better part of his life studying the Sumpter Valley Ry and logging lines. For a career he was an engineer with SP then UP for the last few years. He traveled to the Sumpter country on his vacations starting back in the 1960's and was able to talk to former SVRy crewmen along with folks retired from the woods lines still living. He photographed many structures that were still standing in the woods that are now gone. After retirement he moved to Sumpter so he could devote himself to exploring the logging lines always keeping the search for the lost locomotive alive. In any event he passed away a few weeks back so those of us that emailed old photos and historical topics for discussion with him regularly feel his loss considerably.