I’m saying that anyone watching the cyno will have some idea who is going to come through, like for example a cloaked scout for a ganker group.
Also strictly speaking you don’t need to dock for 15 minutes, you just need to dock for the duration of whatever Jump Fatigue you have, since jumping to a Cyno that’s going to make you go Suspect while already Suspect has an absolutely microscopic cost associated, especially since you’ll be undocking from a station or Citadel when you jump.
Also most systems are within one jump in High Sec anyways, so the odds that you wouldn’t be immediately docking up anyway are minimal.
Also going suspect does not prevent you from docking. The one that prevents docking and jumping is a weapons timer. If I steal from someone’s can or have a Kill Right activated on me I can immediately dock with no issues.