In reply to UKC Articles:
Very interesting, but probably wrong. Grades are subjective, the hardest grade is the one only the best can do. This is theoretically infinitely hard, as it is impossible for all but the one person who can do it.
Moreover, if you work on your weaknesses when at your limit, you necessarily become worse at your strength. Working on powerful climbing styles might build a core that generally aids slab climbing, but for the very thinnest moves you need to lose all extra weight/muscle. In other words, being an all- rounder inhibits the difficulty you can attain in your natural strength.
Obviously as it's subjective there will be a perceived equivalent between the hardest amalgamation of styles and the hardest problem of a pure style, but I'd suggest this is a bit flawed if you're trying to talk about the hardest moves possible.
My understanding of bouldering might be a bit lacking, but this is certainly the case with trad crises.