I disagree with this. You can rebase your branch and then do a "no fast forward" merge. You'll end up with something like:
* Merge commit
|\
| * My branch commit 3
| * My branch commit 2
| * My branch commit 1
|/
* Base
Notice I have not "done away with the merge commit".When you rebase your branch on top of "Base", and then try to merge, git will by default do a fast-forward merge, but you can prevent it from doing so.
It is as though you created your branch, did your work, and then merged it back in so quickly that no other branches were created in the meantime, and if we ignore what I personally did on only my own computer, then I am still following Gitflow.