Describe the bug
When the high-throughput hopper transfers items, it should check what is expected to happen for an item transfer using the simulate option, then based on the results it should attempt an actual item transfer. The amount of items it removes from itself should be based on the results of the actual item transfer, not the simulated item transfer (under certain conditions when using other mods, the two can vary); currently it trusts the simulated item transfer, which while fine for vanilla applications, can cause item deletion in heavily modded environments.

As an example of somewhere that this caused trouble, see Crossroads-Development/Crossroads#183

Issue may also have applicability to regular sorting hoppers?