i have a few differences between speech in life and dreams:

i have a very very slight stutter in real life (few people can even tell i have one), but anyhoo, i have never recalled stuttering in a dream. there are times when i can't talk but that doesn't have to do with stuttering.

in terms of thinking for verbal commands i often don't say exactly what i want. it is like my mind is too slow to think of the right words. so i yell something that is kind of right but as long as i have the right intention in my mind it often works anyway.

when i sing a song i know in a dream i even know parts that i don't know in real life. so i am pretty much freestyling after awhile. and my freestyling is AWESOME. i don't know if it makes sense, but i easily rhymed when i needed to. in real life i am really bad at it.