Don't let the race be dictated by heroic or normal switching, especially when it comes to "linear" progression. The following rules should be in place (for LINEAR) progression:
- If you kill a boss on normal, all of the remainder bosses can only be killed on normal.
- If you kill a boss on heroic, heroic progression remains, but once you have switched to normal mode and killed a boss, you can not do any other heroic bosses.
Given how long it took them to down the 2nd and 3rd bosses (no 10v25 arguments here), it looks like difficulty is a bit out of sequence. The world first race has been tainted by now, and many streams have been discouraged from further putting in attempts on the first boss, taking suite after Arctica.
Please put faith back in the world race by taking these things into consideration.