He's confusing the simple past verb form and the participle. In the English weak verbs, they look identical, but they are used in different tense/aspect/voice s

He's confusing the simple past verb form and the participle. In the English weak verbs, they look identical, but they are used in different tense/aspect/voice structures. Simple Past: He developed. He drank water. Participle: He has developed. He has drunk water. Claiming that it's ungrammatical in standard English to form a present/past perfect tense/aspect with a helper verb plus the participle...! It's nonsense of the highest order. This is epic-level peevery.