A classic of huge proportion. I remember it well. My friend at the time played it constantly. Great cover too, a UFO, brilliant colors. It was the perfect joint smoking album. A few tokes, leave the album on replay, drift away.
I stumbled upon a quote that amused me. It was a post from another site about somebody who enjoyed "Foreplay/Long Time on the big system". Now, as somebody who was pretty much tuned out during the 70s (something about being an engineer/geek) I don't know that I ever heard Boston on the radio 'back in the day' so I looked at the post and immediately thought of something other than a pop/rock song. The thing is, any deliberately Freudian statement from this woman would be SO out of character as to be unbelievable. I tried googling the line but the word 'foreplay' pretty much skews the search results in directions I didn't want to go. I did find a reference to a build your own preamp kit but I never did find lyrics on my first attempt. I had to break down and ask her what in the world she was talking about.
It's funny how innocent statements can appear less than innocent depending on who is speaking and what the context is. "That couldn't have been double entendre - I'm pretty sure she doesn't know any French."
And for the record, yes, she was referring to the song by a group called Boston. She just couldn't imagine how anybody else could read the post and not immediately know what she was talking about.

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