You have sound reasoning, as always; still, when you need a lawyer and you don’t have time to teach one how to think about homeschooling and how to represent you, HSLDA can be very useful.
I think of them as witch doctors for when a demon attacks. Your regular GP doesn’t even believe in demons. The witch doctor has a wagon full of effective exorcism tools. He doesn’t even need to open a bag in some cases, he just says “Begone!” and they be gone. :)
Most of the time all it takes is a phone call or letter from then and the government school demons evaporate.