Agreed on the first part. You have to know there's a code, then somewhere in the message, there's a clue as to how to resolve it and verifications you're on the right path. With the Q messages, there was a very clear and logical decode, but often you had to have certain mathematical knowledge at baseline to recognize the ciphers and coding strategy. There was a guy who posted as SerialBrain2 on Reddit who did good decodes. Me personally? It has been 20 years since I last took a math class. Typically, when I see random anons try decodes, it's nonsensical garbage with lines flying everywhere, but no clear logical progression from step to step. If I can't follow it, I don't give it much credence and move on. It may be right, but I'll have to default to letting the news unlock and having future prove past. If the "decoder" can't logically explain the decode, it's worthless to me.

On the second part, the parentheses don't matter in your expression. In the order of operations, it's all addition. Whether you add the 5+4 first or the 4+8 first is completely irrelevant. You'll get the same answer. Parentheses only matter when you need to violate the baseline algebraic rules of order of operations.

The adding of digits to get to 17 is a very common Q motif, and a clue that you're on the right track on a decode.