[glag0lit]

Oh it really is just a summary, and no commentary as to whether TFA was long-winded or not. That's left to decide for each individually.

[w8rbt]

When you write tl;dr followed by a very short summary, doesn't that itself imply that the article was long?

[slight]

tl;dr has also become a general shorthand for a summary.

[simcop2387]

It's almost an abbreviation for summary!

[tome]

The summary was certainly shorter than the article!