Can someone confirm what the contents of refs/heads/master means?

I'm using git-svn to interact with an SVN repo that has branches.

After my clone via:

git svn clone $REPO/main -T trunk -b branches -t tags

my 'master' branch pointed to one of the branches in svn and not to
the main trunk. (my .git/config looked correct for svn interaction,
i.e. trunk pointed to the right place).

So, I overwrote refs/heads/master with the contents of refs/remotes/
trunk (i.e. the SHA-1 of the svn trunk).

Things seem to be working; git svn dcommit commits to the trunk and
git svn rebase updates from svn's trunk.

So, I want to make sure that refs/heads/master actuall does, in fact,
point to the head revision of whatever branch is considered "master".
Can someone comfirm this (or provide the actual explanation if I'm
wrong?)

Thanks!

Dave