I find it interesting to knowing about it. But when people start saying stuff like "you only get myofibril hypertrophy when you lift below 5 reps so you dont get a lot of size", which is something you will hear a lot of people say, things start to go wrong and it starts to become something its not and people get confused.
The reality is, if your muscles are getting better, you get myofribril hypertrophy, sarcoplasmic hypertrophy, as well as an increase in connective tissue, glycogen stores, fat in between muscles and I think a few other things as well.
You can probably find books or studies that talk about rep ranges and where the focus of the hypertrophy is, but I it varies from person to person.
If you didnt get all of them, then you wouldnt get stronger if you lifted in the 8-12 rep range and you wouldnt get much bigger lifting in the 1-5 rep range. I think a lot of those misconceptions about rep range and size/strength increases come from overcomplicating things like this.
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"When in doubt, just get really, really strong. It tends to cure most problems in training – and life." - Wendler