I've been known to do that, but never in a million years was it due to me having any overfill. It was simply looking at the forecast and seeing lows of 52°, then 45°, then 33°. No way I'm dragging the 20° TQ, so I pushed the 40° that last night and it did fine. After hiking almost 50 miles I was glad. A bonus was having that overfill and knowing it didn't hurt and probably helped that last night.
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