Added GP info and desynthesis recipe. Although I'm not sure why you can get silk thread out of this recipe without any silk being used in the ingredients. ??
Actually, RDM and BST would be the only ones to want these. Maybe DRK, but they don't really rest MP. Also, you would have to drink a Silence potion, then eat an Echo Drop every time you wanted the extra HMP. Considering all the other options for HMP, this would be a last resort.