If I do not use the AJA card in my workstation I edit 4k with no problem. But as soon as I jump over (dynamic link) to after effects to add some graphic or titles premiere gets long rendertimes before you can playback the clip. As much as I like to stay at 4k all the way to the export, this is not practical for all projects.
Is there a good way in premiere to Edit in 4k and then render the edited media in the 4k timeline to 2k with handles. Import the 2k media to a 2k project and ad titles etc. Then export the final master to 2k.
To summit everything is pretty painless in premiere even to ad graphic but after dynamic linking I get a nasty slowdown.