You’re confusing concentration with amplification, and you’re not explaining how you think bed springs could cause concentration despite having no similarity in form or action to your examples.
> "despite having no similarity in form"
When you get into bed, your weight curves the bed springs with you at the centre of a dish-shape. Is that not a similarity in form? If you want to go down that route, this image of bed pressure points[1] shows the most weight and curvature around the hips and thighs, areas the article claims are most affected by melanoma, and less curvature around the legs, neck, head.
I am not making the claim that this is connected or significant, I am wondering how you can think that bedsprings don't curve around a person?
[1] https://i.pinimg.com/originals/1f/fd/bb/1ffdbbfebfd1f54804b9...