I wasn’t originally sure why Shinshire was playing Uzzu as the champion for this deck. Why not something like Renner or Dreaming Fox? Then I noticed the Something Borrowed. When you play Something Borrowed, if you take a non-Blood or non-Sapphire card you won’t be able to play it since the thresholds of the card will remain the same. However, thanks to Uzzu, you’ll be able to play the card by gaining the missing thresholds.
even though it's possible to shardfix, 90% of charges are either for faster bride or for first sapphire (sometimes second for ascension), since the only sapphire sources in the list are 4 cunning wells.
the main purpose of something borrowed is countering constants/artifacts, playing it as removal only as emergency.
also if your lib is thin (or ascension is already on hand), there is point in getting ruby from 2nd charge for that juicy removals