I have noticed that my seatpost slowly lowers itself (~1") over the course of a week or so of commuting. I weight ~275lbs and ride a stock LHT (as far as the seatpost tube is concerned). The local shop used grease in the tube as a protectant for the steel frame. The post is held in place via an allen bolt collar (torqued to correct spec). Any thoughts? Should I remove the grease where I'm trying to clamp? Yes, I know grease is slippery but I'm also concerned about developing rust inside my frame. Is this a Clyde issue where we just need to adjust saddle height every so often? Thanks!