This can be reduced to a simple mathematical equation:

    (risk of hand rolling AES * risk of poor implementation) > risk of poor implementation

Also, if your assumption that the likelihood of introducing a catastrophic flaw is 1 was correct, there would be no correctly implemented crypto anywhere (although it would make the above equation false).

I agree with the nature of your arguments: crypto must be treated with care, and must be vetted by experts. However the whole "DON'T DO CRYPTO EVER!!" mindset is a lot more harmful in the long run. It's a powerful and dangerous tool, but it should be documented and understood instead of making us cower in fear.

Sorry, I missed your reply to this. In case you do ever read this, my point is that:

    (risk of an amateur hand rolling AES * risk of poor implementation by an amateur) = risk of poor implementation by an amateur + epsilon = 1

Even experts make mistakes in these things, but amateurs don't even stand a chance. An amateur will make more mistakes doing both, for sure, but there are bound to be enough catastrophic flaws that it simply doesn't even matter at that point. More real-world attackers are going to try and exploit your abstractions on top of AES than try to exploit your AES implementation itself.