Yes, your understanding is correct. I don't remember details about the form now but it was common mailing address and different physical address (address of residence). In our case, mailing address was used to get common USCIS location. Although, I was a little concerned, I never gave much thoughts to it because we had many docs to prove we knew each other for long time and were husband and wife. Not sure how far the two states are in your case but may be you travel to see each other frequently. If you do end up getting RFE or get asked in Interview, may be you can show proof of the travels to show you visited each other frequently and the only reason for living in two different states is because of work and nothing else.