Welcome!

Can confirm RS3 pottery is broken in all locations. It wont withdraw my preset from the bank even though the "preset already set" option is checked. Sometimes it removes random items from my bank instead of soft clay.

I seem to have an answer for the drops. It only drops when you have the spell high alch in the action bar. If you make it navigate through your spells, it never drops. However, that way is WAY slower and provides much less money and experience. If you want it to be efficient and use your action...