On the other hand, quality of Adler32 is hardly an valid argument here, as HTTP without compression does not use any checksums whatsoever. The fact that it's no

On the other hand, quality of Adler32 is hardly an valid argument here, as HTTP without compression does not use any checksums whatsoever. The fact that it's not consistently implemented is. By the way, Adler32 I don't think that it's right to call Adler32 broken, as there are much worse algorithms in common use (TCP checksum, for example), and limitations of Adler32 are widely known and are not too relevant for this application.