i tried small pieces and one extra cotton layer. it worked very well, i extracted fast. It's a bit more fiddly, though. it needs further testing .
It certainly is a pain to prepare, though some hash much harder than others. The ones that crumble into larger pieces, I do that only a flat hard surface, then once it's cooled down it hardens a little, and can be crushed gently into smaller fragments. Sometimes gently chopping it with a blade or similar breaks ti up fairly well. Bottom line is getting the best surface area to the volume, and the smaller the bits the better that is, plus the hot air flows better through the bowl giving a more even heating.
Also, once you've crumbled/crushed it into a 'powder', if you put a thin layer of cotton at bottom of the bowl, then just sucking the hash up into the bowl works very well without tamping it too much. I don't usually even bother with cotton on top, I just keep the Tempest pointing slightly upright or horizontal so the contents don't spill out into the head (I use mine in the Wand horizontally not vertically for this reason, and it also keeps the cap far cleaner as a bonus).