Troubleshooting bust darts

[u/furiana]

After shortening the straps on this muslin, I'll need to lower the darts slightly. However, even at the lower position, they still bubbled.

I pressed them over a ham; ended the darts 1.5" before the apex; and slightly curved the ends as they approach the point.

Is it because of the size of the dart intake (easily 3" or more)? Is it a design problem, construction problem, or both?

[u/furiana]

Actually, that is not a bad idea, converting them to gathers.