Gazza wrote on Jan 14
th, 2013 at 6:41am:
That's Brian playing (steel guitar). We were sitting around in a circle on the floor, singing and playing, recording with open mikes. That was the last time I remember Brian really being totally involved in something that was really worth doing. He was there with everyone else. It's funny how you remember - but that was the last moment I remember him doing that, because he had just lost interest in everything.
- Mick Jagger, 1995 (from timeisonourside.com)
Song was recorded in May 1968, so maybe a bit early for it to be written as a 'bon voyage' as he hadnt reached the point of no return with the band by that point, but I can see how it can read like it was.
Even though it wasn't the point of no return, I think the writing was clearly written on the wall by then: His time with the band was coming to an end. He was pretty damn distant from them all at this point. He was already marginalized from being the leader, his mental and physical health were fading before everyone's else, Anita had already ditched him for Keith, which broke his and Keith's bond permanently.
While it may not have been written with him specifically with mind, I think seeing how he was falling and fading out of the picture slowly had to have some sort of emotional effect on everyone who once loved him...Maybe it was a subconscious influence.
I think, as detached as Mick tries to seem or seems at times, I think he probably felt a lot sadder about Brian's fall than he lets on, and certainly more than Keith did, maybe even more than he was consciously aware of...
An example of this being Shine a Light. That song was written in March 1968 and was clearly written about Mick's feelings on Brian at that point, his sadness over it all....Who's to say the same sadness and bittersweet feelings about Brian didn't shadow No Expectations as well? It was written within the same period....
I'm just saying a song doesn't have to be explicitly about one subject or another or be influenced by one thing solely. It could simply be that Mick and Keith wanted to try at doing a Robert Johnson type song...With some obvious inspiration lyrically and melody wise unfolding before their eyes, perhaps without them realizing it consciously.
Was it? First I've heard of it, if so. Not saying you're wrong, but I've never read that anywhere. It was recorded in 1970, although there's rumours of an early version from March 1969 (in which case, the lyrics may or may not have been written by that stage)
Your last paragraph touches on a good point. People tend to oversimplify Stones lyrics as being specifically 'about' one thing. Jagger isn't really that much of an open book emotionally. A lot of his lyrics (and Keith's too, to an extent) tend to be multi-dimensional. Songs like 'Worried About You' for example. As much about their own relationship as about a male-female one.