Didn't only Mark/// (total flop - guys@empeg, don't take it as role model) introduce slashes?For what it's worth:
][, ][+, ///, ][e, //e, //c, IIgs, IIe*, IIc Plus*
(in chronological order, if I'm remembering them correctly. * = I don't remember if these have slashes or I's)
The slashes were introduced into the ][ line with the Enhanced //e - which is the easiest way to tell the difference between an enhanced one and an unenhanced one.
(if you're wondering why I know this stuff -
http://apple2.tffenterprises.com/. :)
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Daniel M. Zimmerman
Mk.2 #060000058, 36GB, Red
Mk.1 #00101, 10GB, Blue