I was in Copenhagen Central and noticed the train to Stockholm departs from Track 26 (per signs) a 15 minute walk along Track 3-4. The existence of C to S seems to be noted ONLY on a monitor at Track 3-4. On their main departure screens this train shows as C to Malmo (with a stop in Copenhagen Airport). Taking an earlier train to C-Airport, de-training and then boarding the C-S train on the same platform .would involve MUCH less walking. [C-Airport has only 2 tracks.]
Why do they make things so complicated?
While platform 26 is located further away from the main building than the other tracks, the 15 minutes sign is pretty overestimated (if you are not limited in your walking speed) - it takes maybe 5 minutes from the main building to get to the platform. If you are changing from another train at the central station (regional trains, S-trains) and know which direction to go (towards the bridge in the south instead of the main building) then there is a good chance it's not even a longer walk than changing to another platform or walk to the buses in front of the main building.