What is the difference between git subtree merge and git-subtree
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I've just found git-subtree tool that some time ago became a part of main git repo
https://github.com/apenwarr/git-subtree/

However I don't fully understand what functionality does this tool provide over the already existing "git read-tree" + "git merge -s subtree". Is the only purpouse of git-subtree - making the resultant commit history look better or does it have more functionality that I've overlooked?