I am finding this conversation interesting. I have a Velocity Points J Class booking to the US later in the year on VA with DL connections in the US. It ended up being a very complicated process and I provided extensive feedback to VA, who acknowledged the issues well.

One of the key issues I am facing (and concerned about), I ended up with 2 PNRs and on the way out a DJ/VA connection at BNE (return direct to SYD) with the PNRs for the DJ/VA sectors and the other for the DL. I wanted assurance that I could check in my bags at SYD domestic all the way through to my destination (which will have 3 transit points over two PNRs due to the VA system and the connection in LAX to DL will be Y class as I could not get F - concerned about fees with DL) and it was indicated to me that this will be ok.