Not possible, or??

Very possible - in fact, the first LaserDisc's ever offered in 1978 had several titles that were in analog surround sound. Dolby Stereo, used in theaters on 35mm film since 1976 is 100% analog surround and in the early 70's the record companies introduced quadraphonic (4-channel) albums - in fact, Dolby Stereo was a direct outgrowth of the failed consumer systems. The CBS/Tate SQ system is capable of encoding up to 10 channels of sound within a 2-channel backwards compatible stereo mix. Plus and minus 90 degree phase shifts are used to encode the back channels and sounds are placed between other channels based on level - so level and phase are the typical way analog surround is encoded. The decoders are very complex because they must work so fast 'between the notes' that the ear doesn't hear the action taking place. They create the impression of multiple discrete channels or sound by out of phase audio feedback and gain-riding,

In regards to LaserDisc, when CX Noise Reduction is used, the FM analog tracks have frequency response and dynamic range that is superior to LP's, Compact Cassettes with Dolby c or S and VHS or Beta Hi-Fi VCR's. With a well made decoder and properly encoded LaserDisc, the 3 front channels can be indistinguishable from discrete magnetic sound most of the time. Dolby Labs has some excellent papers on analog surround on their website, so if you want more information, I'd suggest you start there

Not only possible, but typical. Most LDs have an analog surround track.

Interesting, I'd never really thought about it before.. But it just donned on me, that at certain times, when I think I'm watching an ac3 film and see the ac3 light on, however my receiver is on analog.... Yet I could swear I'm hearing surround sound.

Yup, regular old matrix surround doesn't need to be on a digital track. See the attached for an example.

Hell, weren't some VHS releases in Dolby Surround?

Well, 90% of all VHS Tapes have it, and Usually one of these terms:

*Stereo
*Stereo Surround
*Stereo With Surround
*Dolby Stereo
*Dolby Surround, etc.

In addition, Dolby B Nr noise reduction and on some older casettes, Dolby B was Incorrectly Labelled "Dolby System"
(it's true, i got several cassettes and VHS Tapes)

Also note, the very early cassettes (pre-HIFI), Were Linear Stereo.
(i have the 2nd release of Star Wars)

"Dolby System was right!
It was there already before dolby surround came