Years ago the dashes were allowable and then they were not, and I'd love to see the dashes made "usable" again. Many customers (and my existing company now) used dashes as separators in Fixed Asset ID naming and now pre and post the GP version where that changed, they have a horrible, non-sortable list of Asset IDs, some with dashes and some without.

Dashes are still possible when creating assets via eConnect but not in the UI.