Revert "Merge pull request #277 from hjelmn/btlmodrev"

This reverts commit 29e64c3defe170a8fdc891cf32ecb471ff147303, reversing
changes made to 4c8fa17234bcaab07460fb12fbf826ceee4f8df2.

This brings back the btl changes.

Do not merge this commit until after Dec 5.