OK, I have just realized a misstake I have done. I claimed that a TC drop would not fail to produce an item and hence I have ignored that possibility for the chest drop function. That is not true however. Since chest TCs has a no drop possibility, we have a small chance that none of the 4 "drops" is an actual item but a no drop, and we will then have in some cases additional possibilities I omitter since the itmes test in the "magical+" test is often also tested for being no item (which happens with 4 no drops). I will try to look over this and add corrections for this, but it will have to wait a day or two since I am bussy now.
There are three types of people in the world. Those who can count and those who can't.