Got another one...

[Kris Ford]

Here we go again...

1966 Gibson SG Standard w OHSC 711106002569 | eBay
Here's one instance I actually use the SN# LOL..307857..my most reputable source has this as either '65, which it REALLY isn't, or '67, which is what I thought..maybe I'll ask the seller to send multiple pics of the pot codes and control cavity... I would LOVE to see what's there..Guessing that maybe the pot codes could be very late '66..
Still wanting to see a legit true '66 with the large guard and witch hat knobs..not saying there isn't...but have never seen one...

 

[Mike Leaf]

They should eliminate the serial numbers and just put the date and
time it comes off the line on it instead of using a "secret code".
Either that or not bother at all. If the guitar feels and sounds good
it doesn't matter to me when it was made. I'm not a collector.

Well, Gibson actually did just that in 1978.

And they still use it on regular models (not reissues)

Not the time though, but the date is available from the serial number.

You can also see the guitars nr of that days production, giving the instrument a unique ID , which is very important
for instance if its stolen.