Question regarding Fast-Mode
I have tried mosdepth with and without fast mode (-x) and was surprised to see the large differences I am getting with the 2. 

In my (small test), it seems -x is giving results more comparable with samtools depth (which surprised me

Can you explain better what exactly is different between the fast mode and the non-fast mode and why are counts on "slow" mode less comparable with samtools? I expected the opposite
  