[OrsonSmelles]

Alternating or stochastically varying pronouns in your examples used to be a common way to make an effort at inclusive writing, usually preferred aesthetically to constructs like `his/her'. (The style before that was basically to use masculine pronouns for hypothetical people in every single case and deny that there was anything to question about that.) I think I agree that the modern semi-standard of using `they' for examples where gender is irrelevant or unknown is strictly better, but it's hard for me to summon a lot of contempt for someone who goes with a different/older habit.