this is more like a 'double-sided running stitch' ....but! you could also do this with a chainstitch, and loop back each stitch, and on each side, to make the most durable construction.
That's sounds about right I've used it repairs to a denim shirt pocket de seaming I can confirm that it much stronger then the original machine stitching.
Is it Saddle Stitch?
http://www.instructables.com/id/How-to-saddle-stitch-leather/
http://after-the-denim.blogspot.co.uk/2011/11/how-to-saddle-stitch-like-hermes.html
this is more like a 'double-sided running stitch' ....but! you could also do this with a chainstitch, and loop back each stitch, and on each side, to make the most durable construction.