Ok, I'll play along. ;) The moist, hot environment improves oven spring by transferring heat more rapidly to the dough (moist air is more thermally conductive than dry air), keeping the dough surface from drying out and getting stiff. It improves crust quality by gelatinizing the starches on the surface of the dough, causing them to brown better, and form a more distinct "crust", rather than just a skin of browner bread.
To get more steam in your oven, in addition to the simple methods you noted, spritzing and pans of hot water, you can:
- Bake inside a vessel like a dutch oven preheated in the oven. Gives both thermal mass for browning, and traps naturally produced steam around the bread. Remove the lid for the last 10 minutes of baking.
- Cover the baking bread with a large bowl or pan for the first 10-15 minutes of the bake to trap naturally released steam.
- Use one of several commercial steam injection kits (most look like a steam cleaner that allows you to blast some steam manually into the oven when loading).
- Build your own steam injector, like this handy baker. The gist is that they use a pressure cooker with a flexible metal hose attached to an output port and directed into the oven. Boiling water in the pressure cooker produces steam. Pre-steaming the oven for 10 minutes before baking and for the first portion of the bake produces impressive results.
In addition to getting more steam in, you can improve the crust and oven spring by using delayed or cold fermentation, which creates more sugars (better browning), and more extensible dough (better oven spring).