I agree, though fwiw, parser developers have found the memory offsets for a lot of these things, so parser accuracy is considerably higher than it used to be (and they can also probably be considered more than parsers since they're doing a lot more than just parsing the logs).

You can verify this with the newest FFXIV-app by joining a party with a summoner and have him DoT'ing a target dummy. The "parser" will accurately record his damage, and the only way that's possible is by hooking into memory.