That's what I was getting at. I thought if I went LR -> PS there was no way to avoid creating something like a Tiff file to go with the original RAW file.
You are correct. The slight confusion is one of vocabulary, as in what is meant by the word open. One could go to photoshop and open a raw file, and it would simply automatically launch the ACR plug in to create the tiff or psd file. So in a way of speaking you could say photoshop opens raw files.