There is an interesting communication problem here. If I could guarantee that every candidate would read my blog, I'd happily point them to an essay like this,

There is an interesting communication problem here. If I could guarantee that every candidate would read my blog, I'd happily point them to an essay like this, and then in the interview we could work on something meaty, like pattern matching. That would suit your second recommended strategy. But I wouldn't want to write an essay like this, and then favour those candidates who like to read Hacker News or follow me on Twitter. We're trying to select for talent, not for membership in a tribe :-) So we're retiring this question, and we already have a few replacements that we use for many candidates. But I won't blog about them, in an attempt to hew closely to the first strategy you suggest.