There's two possibilities..

1. cprog just hasn't fixed it yet
2. cprog wants people to come from the other rb but not leave this one.

either one would be stupid; both sites are technically cprog's so he should look out for the well-being of both. And when someone wants to leave this site... if they don't realize there is another Rb, they will go to a different site altogether. Therefore hurting cprog's member count. So all he can possibly do by not linking both rb's is hurt his member count - it might not hurt it much, but it will .

that is all .