A lot has to do with approach.
. The tune is so iconic, same with the solo, that I feel uncomfortable playing it. The opening riff is such a unique one, that to leave it out and still call it "Just the Way You Are" to me, is like a restaurant selling a Rueben sandwich without the corned beef. The 6th's in the Gm and Bm chords Joel uses colors the tune in a special way and to not play them also really stood out to me.
Absolutely, Bill...it is a tune that requires more than a bit of work to pull off close to Joel's version. I spent weeks getting the sax solo close enough to the original where I was finally comfortable enough with it to play in public...the addition of the 6ths to the Gm and Bm chords is necessary in my opinion, to give (or to sustain) the tune's twinge of melancholy.
The style I use has the signature Intro, and it allows the player to repeat it...I always start without, and kick it in after the first verse, but, to leave it out entirely, wouldn't work for me.
However, I still like Gary's version...perhaps it's the vocals that make it work...he doesn't try to sound like Joel, so it does seem to give him some artistic license.
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Certainly, the tune itself, seems to have crossed into the "Standards" category, albeit, a "new" standard. Diana Krall does a nice rendition.
A very well written song, to be sure...and my favorite Billy Joel tune...another I like to play, is "She's Always A Woman"...clever chords and lyrics make it a lot of fun.
Ian