Dan may be random, but he's no "random security researcher". And he has, in fact, hacked "just about everything" a time or two by discovering and exploiting common mode vulnerabilities.
His point of view is worth listening to.
His point of view is worth listening to.
He never says there aren't any. He says there are surprisingly few.
He didn't say "it's is perfectly 100% secure", he said "BitCoin surprised me" and "the core technology actually works [] to a degree not everyone predicted".
None of his published work seems consistent with the skillset that would qualify one to thoroughly audit bitcoin. He tends to stick to higher-level, less technical vulnerabilities.