Reading is a T7 mastery. :)
The point being made was you can skip a 15 fragment event/tournament, not that you should or have to.
Fusion difficulty usually comes down to shards for me. If I can't either skip the last reward for summon rush or the whole of champ chase altogether then the fusion becomes tough. The remaining events are standard in terms of energy and time requirement. The excessive champ training is the tough part about classic fusions. Fragment collectors are often the easiest. These hybrid ones are the worst are they are the most shard intensive and still contain an aspect of champ training (and ascension). I strongly believe they should only be done for Brogni-tier championss