Wording in scientific papers

Ok, I'm reading a paper called "Semantic Patches Considered Helpful." Here's what I find fascinating. It features the sentence: […]We have found that driver code makes up around 50 % of the Linux 2.6.13 source code.. Sic, with no quotation, no source, no nothing. Did they compute that themselves? Measured in kilobyte? LOC? What is it?

On the other hand, the following sentence makes a trivial claim, but then goes the extra mile of argueing why it MUST be true: Because the constants 0 and -1 can be used with [different] meanings in […] code, simply replacing all occurrences
of 0 and -1 with [other constants] is not likely to be correct.

What can I say?

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