Bug: version 2.4 seems to have broken `git clone --progress`

In git 2.3.7 I could run the following command and see progress in the
terminal, despite the redirection of stdout and stderr:

    git clone https://github.com/oconnor663/dotfiles --progress 2>&1 | cat

As of 2.4, that command no longer shows progress. When I bisect, the
responsible commit is 2879bc3b0c3acc89f0415ac0d0e3946599d9fc88
("transport-helper: ask the helper to set progress and verbosity
options after asking for its capabilities"). Can anyone suggest a
workaround?

-- Jack O'Connor