This trend in HW of normal mode primals being near completely different fights than their extreme versions is terrible design. If a player were to go from Seph normal into SephEx, they'd be completely in the dark on at least half a dozen mechanics.
This makes it very hard to get new players into the fights, much less getting them to clear/farm them. It ultimately shrinks the endgame PuG/Static pool to pitifully small numbers compared to the endgame server population.
The normal modes should teach players how to successfully clear the extreme fights. They should be literally the same fight with the numbers tuned down to allow more room for error.