Japanese 1 The annoyance of "oo"

Is Shachoo spelled しゃちょお or しゃちょう? I was under the impression that if two "oo"s where present I'd have to put a う at the end but apparently that is not always the case.

>>16
I don't see how your point is relevant at all.

1. why would you even romanize しゃちょお
2. I was responding to >>4 ("historical reasons")
3. nothing you wrote refutes the "lol romaji sux" point at all