Hey,
I was trying to add some more information on the diamond drill issue, that if it was empty, it was mining as fast as if it was charged. That seems to have been true only for certain blocks.
I had a full one and charged it with an RE Battery when it was empty, after that it could mine empty as fast as if it was full through rock, cobblestone, iron ore, tin ore, gold ore and coal, for example. Mining through dirt, gravel and redstone was really slow - more like with an iron pickaxe, it still yielded redstone dust though.
I'm opening a new topic because I'm uncertain if these facts come to light and perhaps making the problem remain