I'd suggest just being slightly more suspicious of insulting arguments that make claims about your character sucking (immutably) than ones about the way you've laid out the plan.

It seems katydee may have made a mistake in choice of language here by conflating "yourself" with "your plans". To nitpick, it might better to consistently refer to the thing to be strawmanned as "your plan(s), and not use "you" at all. If one wants to generate an argument to point out flaws in their own plans, strawmanning yourself is like launching an ad hominem attack upon oneself. When somebody is looking to improve only one plan targeted for a (very) specific goal, strawmanning the plan rather than one's own character would seem to illuminate the relevant flaws better.

Of course, if somebody wants to prevent mistakes in a big chunk of their lives, or their general template for plans, strawmanning themselves, then might be the time strawmanning one's own character is more worthwhile.