Ok...lets run through a few things.
Generally good healthy leather=Proper color leather polish (wax) will seal the pores and offer a little bit of nutrients to the leather.
Dirty dried out leather=Saddle soap, a light wipe of neatsfoot oil and then wax.
Clean dried out leather=light wipe with neatsfoot oil and wax.
Scuffed up dingy leather=Strip old finish with rubbing alcohol, and re dye it with appropriate color dye, light coat of neatsfoot oil and reseal it with Fiebing's Saddle Lac Spray. Polish as usual.
Neatsfoot oil WILL soften leather, but, its necessity if it gets dried out, soaked in water and dried or sits out in the sun alot. You don't need much. Warm the leather by leaving it the sun for awhile and then wipe on a light coat and let it soak in.

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