Hehe.. guilty as charged.

Ok, I’ll write something that shouldn’t confuse ;P

Geoff, your sun striking bookcase shot could be a perfect learning environment.
A photographer once taught me that mastering still life photography will help you in all aspects of photography. At the time I had no interest in that genre but he was absolutely right.
A still life scene presents you with the challenge of controlling every element of the scene from lighting to composition to exposure parameters.
I’d have to assume your bookcase was lit from sunlight through a window?

Window lighting is great because it’s full spectrum but varies greatly so you get to experience many aspects of light quality even though you can’t control what the weather will serve up.
Light temperature and direction changes throughout the day and season. It can be direct or indirect, may be diffused by cloud cover or something you put in front of it.
But the directional nature makes it great because it creates highlights and shadows and you can see how it ‘wraps’ your subject. You could try a bowl of fruits or place a willing model next to the window.
You can introduce fill lighting from the opposite side of the window direction with a reflector or artificial light.
You can see how the various metering modes react to the lighting scene.

Study the masters. Rembrandt lighting might have become slightly cliche’d but he isn’t called a master for nothing.

But the most important thing is you are experimenting. Nothing beats making mistakes and getting the chance to try it over again.