Sure seems like this could be the case with the structure of the prompt, but what about capitalizing the first letter of sentence, or adding commas, tag questions etc? They seem like semantics that will not play any role at the end
These are text completion engines.
Punctuation and capitalization is found in polite discussion and textbooks, and so you'd expect those tokens to ever so slightly push the model in that direction.
Lack of capitalization pushes towards text messages and irc perhaps.
We cannot reason about these things in the same way we can reason about using search engines, these things are truly ridiculous black boxes.
Might very well be the case, I wonder if there's some actual research on this by people that have some access to the the internals of these black boxes.