Here are my thoughts:

Her are my thoughts:

Sweat is good! It's a fabulous (and important!) temperature control medium, but it needs access to air to be able to cool/evaporate. A leather band with perforations/holes (like a driver's band) feels noticeably more comfortable when sweating.

Dry leather surfaces more readily absorb liquids than those that have been oiled (beware of Neatsfoot Oil which very easily soaks deeply into leather BUT it also softens it). Also, leather can be coated in water repellents like wax (eg some leather shoe polishes).

Smells are caused by bacteria. Kill bacteria and you kill smell. Bacteria thrive in a warm and especially a moist environment.

Alternating bands gives them more drying time (hurrah for quick release pins).