I found that
Multiple working directories with Git? - Stack Overflow is a very nice feature for recent git version. For windows, I now use the latest git-for-windows 2.9.x version.
I used to maitain several branches for a single working copy, one branch A has many commits beyond the original/git-svn, and one branch B is for git svn dcommit only. Before using the new git feature, I need to check out A or B, and this always need to rebuild A or B after the switch.
But with the new feature for now, I can have A and B in different directories, and they share the same local repo. I can simply cheery pick some useful commits from A to B, and then build and test B, and finally git svn dcommit from B. Very nice workflow.
