To become a licensed professional engineer in the United States, you need a four-year degree in engineering from an accredited university. You must then work for at least two years under the supervision of a licensed professional engineer and must then pass a couple of rigorous licensing exams. Flynt/Wu has none of those qualifications. In many states, he could face civil and criminal prosecution for providing engineering services.
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But Flynt/Wu is cunning. He doesn't attempt to work as an engineer. Instead, he constantly writes and says "as an engineer," which is nothing more than an outright, blatant, and shameless lie intended impress the gullible and deceive them into thinking he has a four-year degree in a difficult discipline.