In cases where the leather is really crazed or cracked and scuffed. Yo might find that the (shoe) polish doesn't shine up or soak properly. In those cases, you might try the 'hot spoon' polish technique (you can google it) but essentially get the polish on the saddle, heat a spoon over a flame (not red hot!) then smooth it over the polish. it discolours in a panic inducing way initially, but it allows the melted polish to soak into the cracks. When dry, you can get a decent shine back on it.
For the advanced polishing, you might mix the polish with beeswax, which gives you a hard finish. Obviously in all cases, try a small patch first.