Leather - funny bugger....
Yes Leather needs to be fed as it is to all intents and purposes skin. So skin with moisturiser is better yes.
Now you have three choices, you can use saddle soap or 'dubbing' which is predominately made up of petrochemicals which if used excessively can cause the the leather to 'break down' and become overly soft (stretch marks) or you can use a wax like Grangers 'G-Wax' which is a high grade bee's wax and works better. Although both can leave a degree of residue which is obviously not good for sitting on.
The third choice (and the one i would use) is a specialist 'car upholstery' product that is designed for leather car interiors.
Your megulars or similar....... With leather conditioners you will find that most are sold for a particular purpose with chemical and residue properties to match.
John (Part-time bootmaker)