Here's another "What If?" question for you: what if "In Through the Out Door" was released as a double, rounded out with the 1978-era "Coda" tracks and "Walter's Walk" thrown in for good measure?
The original ITTOD clocks in at 42:25 and with the four tracks added, the revised total (by my math) is 60:50.
That's a little short for a double, but at 67:07, "Exile on the Main Street" isn't that much longer.
Something like "Swan Song" could have rounded it out nicely.
What do you think?