21 pages, is not a plan. The Scottish independence plan was 500 pages or something.
Also, that "plan" merely states they will trigger article 50. Not what they will do after that. Which is the important part of the whole process. There was no talk of soft or hard brexit. No talk of how much it would cost, no talk about anything other than "We'll trigger article 50". Which it actually turned out, the plan was flawed because they legally couldn't do it and had to create a new law.
Also, that "plan" merely states they will trigger article 50. Not what they will do after that. Which is the important part of the whole process. There was no talk of soft or hard brexit. No talk of how much it would cost, no talk about anything other than "We'll trigger article 50". Which it actually turned out, the plan was flawed because they legally couldn't do it and had to create a new law.