Reason for using different sleeve lining?

[Mark Seitelman]

Generally, each tailor each has a "signature" stripe. E.g., Davies uses a Bengal stripe in either dark blue or grey depending upon the coat's color. It is a little touch of individuality and "advertising". It also is a little touch that sets apart bespoke from RTW.

Are you referring to a signature stripe being the "little touch that sets apart bespoke from RTW" or simply the act of using a different lining? If you are referring simply to the use of different lining for the sleeves then, unless RTW has changed its approach in the last 5 to 10 years, the evidence of my wardrobe suggests that simply a different (cream/white) sleeve lining is not a particularly reliable differentiator from RTW. Of the 14 RTW suit and odd jackets that I still have in my wardrobe a total of 6 have unmatched sleeve lining.

- Julian

Using a different sleeve lining is just an "extra touch." It is another operation in manufacture which means added cost.

Is the lining a "make or break" element of a fine garment? No. E.g., Oxxford generally does not use separate linings unless ordered by the customer. It's just an added touch and throwback to earlier times when they served a practical purpose.

It is likely that most tailors do not know the origin of separate sleeve linings. They just carry it forward as a convention and tradition. Most would probably say that they do it because they have always done it this way.

[HandcraftTailor]

Realise this is a two week old thread, thought I'd give my two cents anyway.
At Henry Poole I was taught to lining a suit jacket sleeve with the house stripe lining and a sports coat in either a white/ off white or same as body lining. I believe it's traditional a different lining because it was usually a less expensive lining and also lighter weight. Their Court coats is still lined with silk and as the livery tailor explained to me during my apprenticeship, the sleeve lining would be lighter than the body to help cool for comfort.
As to the idea of the white lining because of the shirt colour, refers to a waistcoat inside lining and the not the sleeve.