What's the size of the finished block? Total up the dimensions of the template as printed in the pattern/book and see if they equal the size of the block.
Fir a very simple example, look at a 9-patch that finishes at 9 inches.
1. The template in the book measures 3 inches. 3 + 3 + 3 = 9. You will need to add seam allowances.
2. The template in the book is 3.5 inches. 3.5 + 3.5 + 3.5 = 10.5 inches, therefore there are seam allowances added.
I think older books, and perhaps older teachers, assume that you will be piecing by hand, drawing out your stitching line onto the back of the fabric and cutting with scissors. Maybe even eyeballing that 1/4" allowance as "close enough." (I do that "close enough" now with techniques like folded corners.) Like my grandmother, they may feel it isn't a "real quilt" unless every stitch is sewn by hand the way they do it, so obviously the knowledgeable reader will want to do that too.
Me? Rotary cutting and machine piecing all the way! If I had to hand-piece, I'd make 1 lap quilt a year instead of several. My daughters would still be waiting for their wedding quilts 20+ years later.