Hi Jack!
I'd like to add my 2 cents here. I think there's another way to look at the LoA, summed up and starting from something
Lon Milo DuQuette said in his book
The Chicken Qabalah of Rabbi Lamed Ben Clifford:
"It's all in your head, only you have no idea how big your head really is."
I think the LoA is subject to the awareness and level of consciousness of an individual. If you have a low level of consciousness, you might not be able to discipline your own thoughts, much less direct your thoughts in a coherent and focused manner.
The more able you are to control your own thoughts and focus them in a direction you want, which is a principle of applying the LoA, the more powerful the results you'll get.
Perhaps the highest and supreme level is one where what you intend for the universe at large manifests immediately, but you'd have to be God at that stage
At a lower level of consciousness, awareness and power, we'd be able to use the LoA to manifest changes in our immediate vicinity and areas of attention, but less so in global changes that are outside of our awareness.
2 cents!