Thus spake "Jon Lewis" <jlewis@lewis.org>
The trouble is, it turns out there are a number of networks where CIDR isn't spoken. They get their IP space from their RIR, break it up into /24s, and announce those /24s (the ones they're using anyway) into BGP as /24s with no covering CIDR.
IMHO, such networks are broken and they should be filtered. If people doing this found themselves unable to reach the significant fraction of the Net (or certain key sites), they would add the covering route even if they were hoping people would accept their incompetent/TE /24s. S Stephen Sprunk "God does not play dice." --Albert Einstein CCIE #3723 "God is an inveterate gambler, and He throws the K5SSS dice at every possible opportunity." --Stephen Hawking