Your use case is not unique: I have seen others asking the same question, and for the same reason as you are describing (separating getting data from placing trades). My guess is that many are using the "2 user names" option to solve this. I got the link to the IB page from those conversations.
Thanks @HobbyTrading bit embarrassed that I didn't do the right research myself. Thanks for helping out. I promise to do better next time