Consider removing last para before §2.1.1

[nigelmegitt]

          Note that Section 2.1.2 contains similar text that says "in the client player". After reading the introduction again, I feel that the last paragraph before 2.1.1 could be removed. It was an initial justification of why AD and Dubs are in the same spec but it does not feel necessary or at least could be simplified and used to introduce the next subsections.

Originally posted by @cconcolato in #206 (review)

[nigelmegitt]

The paragraph in question is:

The authoring workflow for both dubbing and audio description involves similar stages, that share common requirements as described in [DAPT-REQS]. In both cases, the author reviews the content and writes down what is happening, either in the dialogue or in the video image, alongside the time when it happens. Further transformation processes can change the text to a different language and adjust the wording to fit precise timing constraints. Then there is a stage in which an audio rendering of the script is generated, for eventual mixing into the programme audio. That mixing can occur prior to distribution, or in the player directly.

I would prefer not to remove this, but would be happy to review proposals to simplify it. I think the link to DAPT-REQS is helpful here, though it is not the only place in the document where this link is made.