In cases where there could be confusion, you might as well put the suffix on all instructions. At the moment, we have no assembler program to ensure that your source corresponds to its machine code or to enforce the syntax rules of instructions. That is why I have made these rules as simple as possible. When I get time, I will write an assembler. Too many parenthesized comments in text can destroy both readability and understanding.
Footnotes are less obtrusive and provide more leeway for comprehensive explanation.
In similar fashion, inline comments distract from the code and are so small they don't explain much. Do not, as I have seen, comment every line with a restatement of what the assembler instruction is doing. Do comment what you put into registers. The actions of a program are better understood at the level of functions and high level control constructs, such as loops and ifs. I have commented every line of my sample programs only because their purpose is to teach the instruction set.