Distortion in Joni Mitchell's "Car On A Hill"

Been one of my favorite tracks for years - I think the songwriting, arrangement and playing on it is just fantastic. However I've always wondered about that horrible clipping which happens about a minute into the song, during the bridge. It really sounds like the master bus was majorly overloaded during this section and it almost makes my eyes water every time I listen to it. For years I thought I had a suspect copy of the CD but of course since then I've heard it from other sources (on the radio, on Spotify etc) and the same distortion can be heard. 
 
So this kind of makes me curious. How did something like that slip through the net? I'm presuming that whenever it was mixed, someone had their eye on the VU meters. Did they just leave it in there for artistic effect or something? Seems strange when you think about the lengths people go to in order to balance levels at their optimum. I've heard of people clipping for artistic effect, but that to me always sounded like when someone taped an album for you and they set the levels too high. 

bitflipper
I'm still trying to figure out how Rush ended up with that horrid Vapor Trails album - surely they're at a point where they can call the shots in the studio, but I'm guessing Neil's biking buddies were waiting for him out in the parking lot.

Don't be too sure about a band's power. I always remember this old SOS article with Tori Amos repeating advice she had gotten from Peter Gabrial on why she built her own studio:
 
http://www.soundonsound.c.../articles/toriamos.htm
 

"Peter said to me 'You've made some successful records, but I want to know where you're going to be in 10 years time. There will be good times and bad times with your record label, and to develop your music you need a workshop, a place to experiment.' I had no idea how right he was going to be. Had I not listened to him, I don't think I would have survived the war with Atlantic Records. But we were here in Martian Engineering, and we were in control and in command of the music and the record company only had access to the master tapes that I gave them. I've heard stories of artists standing outside and banging on doors, screaming 'Give me my #%%$# masters!'"

They pave paradise?
 
My best recommendation on saturation is
 
http://www.fabfilter.com/products/saturn.php