"I am new to this as well, but as I understand it, higher mash temps favor certain proteins that tend to leave more complex sugars in the wort thus leaving a sweeter maltier beer in the end. Lots of folks can give you the deeper answer, but that's the quickie answer"
No, not really.... It is enzymatic action that is responsible for producing sugars. However, proteinase is an enzyme that has the ability to break down beta glucans into glucose at a certain temperature. Proteinase isn't kilned out of modern malt. Then, beta can work on the glucose, producing maltose and maltriose. Higher mash temps allow alpha to do their thing. There are two types of alpha, I and II. They work at different temps. Research German recipes, not Americanized versions. Many times, after a beta rest, the brewmaster will crank up the heat and do two rests, favoring alpha I and II. Boiling down the wort will increase gravity. The more sugar in solution, the higher the gravity.