I don't know why the title of the book is called "casual clothes" because the shirt sloper is perfectly suited to shirts of all kinds. I suspect that the title of the book may have been forced onto the authors by the publisher.
Firstly, thanks for posting this publication. ALL resources, no matter if one agrees with them or not, are great for helping a shirt maker develop their standard.
I agree with you on the title of the book. However, I'd say these days the line between what is formal or classic or casual has become a little more blurred than it was in 1985. I would also say that considering the girth and cut of this shirt that it was the precursor to what we call the 'slim fit' today.
I note that the pattern results in the following girth eases: chest 4", waist 6", seat 7".
Personally I would not dare to offer these girth eases to a client I have never met in person. I prefer to make my slim fit shirts 6"/8"/9" for those that order from me online. Although, for clients I meet in person I have slimmed the shirt right down to 4"/6"/7".
Something I really don't like about this pattern is the armpit shaping. I prefer a slightly higher pit with a more flattened, evened out pit. I guess the styles change according to time and trend.
Over all though this is a valuable resource to those wanting to make a close fitting shirt for our more "athletic" figures.
Have you seen anyone publish or re-print it yet?