When the leather is in such a bad condition that is no longer restorable and we don't wanna end up in "Brooks" (No offense ment) or a doubtfull quality saddle, we can allways use the original estructure and "make" or better said: mold the cover.
In my humble opinion this is a more respectfull way of restoration, I love the above mentioned saddle's brand, but it is just not right for spanish roadsters from the 50's-60's, for instance.
First step is to manufacturate a mold as similar as possible to the original (Better use wood, DM makes an icredible cloud of unbreatheble dust)
My way of making the molds is cutting layers of 18-20 mm. thick and glue them one on tope of another.
After that comes sanding untill you reach the desired form.
Once you've made your choice let it soak in water for at least an hour. Take it of, put it on the mold and start forming, you can use nails or staples. The neck is by far the most difficult part, take your time.
Once you have it is time for dyeing it, do it while the leather is wet with alcohol soluble anilines. This is also the moment for decorations.
I warm mine untill 80-100ºC and leave the leather (still on its mold) for an hour and half, but I contstantly keep an eye on it... some times my wife had to ask me what the hell was I coocking! This is necessary if we want the leather to keep its stiffness.
Sand the cuts and use lacker to make it a bit shiny, Here we have our own brands...
Keep on trying and you will see the improvement for yourself. And in case of doubt you can always look for the inspirational work of the masters, such as Tim, from whom I've learned a lot.
Go ahead! Make a saddle!