OK, here goes. This will probably seem confusing, so I'll explain it the best I can.
I have the Blackmagic Multibridge Pro. I cut on Premiere Pro CS3 with the XDCAM update. As of right now, the Blackmagic Decklink software does not support XDCAM. So, I have imported my .mxf files into an XDCAM project. I then re-exported the files using the "Blackmagic HD 8-bit 4.2.2" Codec. I set the frame size to 1440 by 1080. I set the frame rate to 59.94 to match the frame rate of the original 59.94i XDCAM footage.
Once the footage is exported, I open a Blackmagic preset project in Premiere. I use the Blackmagic Interlaced 59.94 8-bit HD preset for the project. I then import the footage I converted using the "Blackmagic HD 8-bit 4.2.2" codec from the XDCAM project. In theory this footage should not require rendering. However, it does. What is the reason for this, and why is it happening? Let me know if I need to explain this better.