why is "70s/80s" "better" than "1970s and 1980s""?

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I fail it to see why can be better to write 70s/80s (which obviously simplifies to 7/8), when what is intended is "1970s and 1980s". Dondervogel 2 (talk) 20:48, 25 May 2015 (UTC)Reply

@Dondervogel 2: I don't see any big difference between both, but looking at the context, to me, 70/80s is better than "1970s and 1980s". If you're going to discuss it, don't include your edit first. MYS77 04:31, 26 May 2015 (UTC)Reply
Using the shorthand that you argue is "better", without providing a reason, contravenes mos guidelines. There are good reasons to avoid "70s/80s", the main one being that it is ambiguous. If you don't like my (tongue in cheek, but formally correct) arithmetic, perhaps you would like to consider what century it refers to. But frankly, I don't give a damn. Dondervogel 2 (talk) 05:09, 26 May 2015 (UTC)Reply
@Dondervogel 2: I see that WP:DECADE prefers the other format, let's revert it back then. MYS77 05:18, 26 May 2015 (UTC)Reply