Depends on what you think an "average" home brewer is.
You don't need a science degree to get the basics right, try reading the
Braukaiser section on pH he also covers some of the other issues you have mentioned (L:G stiff mash, temperature steps...) and all in a pretty well worked through way that's not too hard to follow.
Similarly being suspect, but think about this, the old traditional bush billy tea, put the water, tea and sugar in the billy - cold - bring it to the boil, result is a rich tea with no bitterness (tannin).
Do the same thing without the sugar and the tannins are going to give you tea bitter and astringent enough to de-enamel your teeth!
The sugar is blocking the tannins from coming into solution, acid in the sparge water does the same thing, this is also why we can boil a decoction, there is enough sugar to block the tannins.