+If
+.I branch
+is prefixed with
+.B +
+then if it already exists, it will be simply ovewritten,
+no matter its existing contents.
+If
+.I branch
+is prefixed with
+.B ..
+then if it already exists
+and dgit actually imports the dsc
+(rather than simply reading the git commit out of the Dgit field),
+dgit will make a pseudomerge
+so that the result is necessarily fast forward
+from the existing branch.
+Otherwise, if branch already exists,
+dgit will stop with an error message.
+