pack.packSizeLimit and --max-pack-size not working?

I'm using 1.6.0.4 and I've found some weird behavior with pack.packSizeLimit and/or --max-pack-size.

Initially, I thought I could just use pack.packSizeLimit and set it to (say) 1 to try to limit the size of individual packfiles to 1MiB or less. That does not appear to be working.

In one case I performed the following set of commands:

# set pack.packSizeLimit to 20 git config --global pack.packSizeLimit 20

# verify that it's 20 git config --get pack.packSizeLimit # verify it's 20

# run gc --prune git gc --prune

# show the packfiles # I find a *single* 65MB packfile, not a series # of 20MB (or less) packfiles. ls -la .git/objects/pack/*.pack

# try repack -ad git repack -ad

# I find a *single* 65MB packfile, not a series # of 20MB (or less) packfiles. ls -la .git/objects/pack/*.pack

So it would appear that the pack.packSizeLimit param is just being ignored??

Then I tested using --max-pack-size explicitly. This works, to a degree.

git repack -ad --max-pack-size 20

# the following shows *4* pack files none larger # than (about) 20MB ls -la .git/objects/pack/*.pack

# try again with 3MB. This also works. git repack -ad --max-pack-size 3 find .git/objects/pack -name '*.pack' -size +3M -ls # nothing

# try again with 1MB. This does NOT work. git repack -ad --max-pack-size 1

# here, I find a *single* 65MB pack file again: find .git/objects/pack -name '*.pack' -size +1M -ls

Am I doing something completely wrong with pack.packSizeLimit? What is going on with --max-pack-size in the 1MB case?