I want to encourage you in this page. But what appears relatively simple can become difficult when you try to prove something.
Take this example. looks heavy. A play at a is more likely. (We do not know the surroundings, so may be OK.)
White might play this way. (Again, depending upon the surroundings.) Now you may say, White has become thick. To which you get the reply, But look at Black's territory!
Rather than trying to prove anything, maybe showing some pro examples would be good. Alternatively, find some DDK examples of where attaching did not work out, or should not have.
I've temporarily put it back the way I had it originally, which might help things a bit, but I will look for a better example and fix this soonish.
Thanks!