maybe you are having a problem because you are calling them RULES... i don't really know many quilting RULES but i do have some great books with wonderful (GUIDELINES) that have helped my quilting get better and better.
and some of the (guidelines) basic...this is the way it's done type of thing...
you asked what if i want to use 1/3" seam instead of 1/4" seam....well, if that's what you want to do for YOUR project...what ever works for you...
but you will have problems if you use (other peoples patterns) because QUILTING PATTERNS ARE DESIGNED FOR 1/4" SEAMS if you change your seam allowance you have to adjust every part of your pattern...that is certainly your choice to do...i think most of us at some point (re-do) the math and change our seam allowances ect...but every pattern you buy...is going to start with the 1/4" so it seems like it would be easier to just find your 1/4"...in clothing contruction the seams used are 5/8" seam...so those of us who started 100 years ago making clothes have had to re-learn and adjust our sewing to apply it to quilting. different applications require different techniques...has nothing to do with anything as negative as (RULES) just has to do with (centuries of experience) and someone writting down the guidelines to make it easier for everyone. :thumbup: