The bug can be replicated using 2 opti benches (The ones you can get in creative) and connecting then using thermal expansion itemducts with the worst servo. You need to in one of the opti benches place a recipe to make something into a block and in the other to make the block into the something. I belive the opti bench of the something must be nearly full for it to work and that it's somehow related on how itemducts with the worst servo move 8 items at a time.

see #111 :P

We will see if anyone discovers the full thing.

So... It's not a bug, it's a feature?

right. This was the whole purpose of the optibench. looping the output and input was never ment to be used this much though.