OK, here is the photo comparison! Three weeks on the Safe Starch. He is taking about 9 days to eat 40lbs now that I've got the delivery method sorted out. Here he is the day I started him on it:
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And here he is today:
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Slightly different lighting and unfortunately I cut his butt off in the first pic but he does appear to have lost weight and his crest is going down. Gained a hole on the girth of his harness. And...only one data point on this, but...he was not at all bothered by gravelly areas last time I had him out on the trail, areas where he would previously sometimes go bushwhacking to avoid walking on the rocks, he just tromped right down the middle.