title: git worktrees vs "clone --reference"
body: <p>What are the pros-cons of using git worktrees vs maintaining multiple clones with <code>--reference</code> flag? The main scenario I am considering is when a developer needs to maintain multiple git repositories on the disk for old releases (release/1.0, release/2.0, release/3.0) because switching branches on a single git repo and rebuilding would be costly. </p>
  
  <p>Using worktrees the developer could have a single clone of the repo, and any old releases could be created as worktrees of the repo using <code>cd /opt/main/</code>, <code>git worktree add /opt/old_release_1 release/1.0</code>. Using reference clones, the developer maintains a main clone somewhere, and uses <code>cd /opt/old_release_1</code>, <code>git clone --reference /opt/main/.git ssh://git@github.com/myrepo.git</code> to create clone repositories for the old releases.</p>
  
  <p>It seems like they can both accomplish the same goal. Are there benefits to one over the other in terms of speed, disk space... other things?</p>