I used to think this would be impossible to do, however with practice this honestly gets much easier. All I can say is stick to it, watch YouTube for speed runs as they use sneaky tactics to carve serious time off of your run.
Co-OP can be a great way to cut the times, but it has to be with someone good. If they are average at the game it will hinder more than help. At least with solo play you can rely on your own skills.
Best of luck getting the gold times