At this point in time, I believe it's necessary for Tableau Desktop to use calculated fields when connecting to R. That said, if someone with knowledge about R were to make the original connection and create the needed calculated fields, they could create an extract that you would be able to connect to and use. Please note, you may need to create additional calculated fields as you try to dive into the data.
If you haven't already read the whitepaper on using R with Tableau, I suggest reading it as it hass some fantastic information on how Tableau interfaces with R. You can find the paper here: Using R and Tableau | Tableau Software
Thank you for the reply. Yes, I have read the link you supplied.
Sounds like it is possible but you really need to know what you are doing with R. The reason I am investigating this is because client wants advanced statistics using R but they only have Tableau Desktop and Tableau Reader and do not have support for R (related to sustainability of the product.)