faq: ssh: proxy is an alternative

Clearly mention that the ProxyCommand is an alternative, less efficient
than using SSH with MPTCP support directly.

Also mention that other commands like scp, rsync, git, etc. can be used
with 'mptcpize run' as well.

Signed-off-by: Matthieu Baerts (NGI0) <[email protected]>

Author: matttbe

faq.md

@@ -245,17 +245,19 @@ workarounds: </summary>
     `mptcpize run`, or set `LD_PRELOAD` to the full path of
     `libmptcpwrap.so.0.0.1`.
 - On the client side:
-  - Prefix the command line with `mptcpize run`, e.g.
+  - Prefix the SSH command line (or `scp`, `rsync`, `git`, etc.) with
+    `mptcpize run`, e.g.
     ```
     mptcpize run ssh example.org
     ```
-  - Set the `ProxyCommand` option to use `mptcpize run`, e.g. by using this line
-    in the `~/.ssh/config` file:
+  - An alternative is to set the `ProxyCommand` option to use `mptcpize run`,
+    e.g. by using this line in the `~/.ssh/config` file:
     ```
     Host (...)
         ProxyCommand mptcpize run ssh -W %h:%p -l %r -p %p %h
     ```
-    This is useful not to require a prefix for all `ssh` commands, or if SSH is
-    used by other tools, e.g. `git`, a file manager like Nautilus, Filezilla,
-    etc.
+    This proxy command is less efficient, because it will force `ssh` to be
+    launched a second time as a proxy. But it is useful not to require a prefix
+    for all `ssh` commands, or if SSH is used by other tools, e.g. `git`, a file
+    manager like Nautilus, Filezilla, etc.
 </details> {: .ctsm}