The uncombed penumbral model explains the structure of the sunspot penumbra
in terms of thick magnetic fibrils embedded in a magnetic surrounding
atmosphere. This model has been successfully applied to explain the
polarization signals emerging from the sunspot penumbra. Thick penumbral
fibrils face some physical problems, however. In this contribution we will
offer possible solutions to these shortcomings.Comment: 6 pages, 2 figures. to appear in the proceedings of the Solar
Polarization Workshop I