I can see this thread is super old but I really liked the topic as its relevant to what I've been looking for and what I'm practicing at this minute.
On a personal note I have a friend who is a Saddler for Hermes and working currently. He told me that sewing machines form an integral part to the luxury industry, specifically Saddlery and bags and leather goods in general at Hermes. However, Saddle stitch is used on all parts of a leather good or saddle that function as load bearing. On parts that do not carry a load or strain and therefore are not integral to its function will often be machine stitched.
Machine stitching and finishing the stitch can be tied hand off or saddle stitched where finishing is required by hand thus combing the machine with hand finishing techniques by leaving thread to work with.
I meet him a two years ago as I was finishing up in Melbourne and about to relocate to Spain. I had a small dog accessories business using machines while over time self learnt traditional leather working techniques.
Saddle stitching is quite easy but beautiful and regular stitching has been a massive challenge for me!!!