Interesting - I had not. It was ages ago I was doing something like what I posted (well before that project ever got started) and it worked "well enough" for what I was doing at the time. Usually I'd run a SOCKS proxy on that second SSH line (-D 4444) and just point my browser at localhost:4444 to route everything home (or use foxyproxy to only route some traffic home).
Looks like sshuttle may have better performance though and provide similar functionality.