Is there a right brew length? There is but it depends on the system and the malt bill. Whether you are a home brewer or professional brewer one of the indicators to look for is around the 4% evaporation.
Achieve that and you can consider the action of the boil has done what it was supposed to do. At the end of the day, and this only applies to home brewers. From what I have read on different forums, and I say this without prejudice, I tend to believe there are those wanting to simply make beer and those who want to brew a beer either better, or on a par with beers they buy. I think that is where the different train of thought between brewers comes into play.
Emma