once you are attending, your teacher will not only place you appropriately - but also catch you up on any area of a level that you are not proficient in. a master teacher can immediately spot areas that might be below level or above level. usually, they try to coordinate all the areas of piano study with each other. this includes theory, sightreading, sightsinging, etc. even though you take other classes to help you in this area - your piano teacher is the likely one (having one on one lessons) to tell you 'you need to work this area.'
there are the rare students that are proficient in every area of a level/grade and adequately pass to the next without having skipped over some important things. musical terms, for instance. basically, the harder levels are also dealing with a good deal more memorization (which requires being able to analyze a piece of music more in depth). also, if you take orchestration - you can see how musicians composed music to sound like certain instruments or voice - or literally be orchestrated at some later point.
getting back to wheaton. i am impressed by the syllabus - but don't think it is necessarily the last word on the subject. who am i to know. but my teacher, who took lessons from julliard - i believe - would be apt to take a piece such as the brahms intermezzos from op. 118 and put them higher (in terms of interpretive difficulty). it might be a figment of my imagination - but i tend to think that high quality music can be astonishingly virtuosic or just plain simple. but sweet. have tone colors and images that it brings to mind. to have a singing line. this seems very basic and simple to beginning students - but the more you study music the more you realize it isn't ALL the technical difficulty. although that is what impresses people the most.
pedalling techniques can be honed in college much MUCH better. i remember the first few years i didn't ask ENOUGH questions about pedalling. this is a very important subject. it makes or breaks pieces much like interpretations. for each composer - there is almost a certain pedalling technique they were using (as well as fingerings to suit their own hand). to find out these details requires not just looking at the pedallings and fingerings that an editor put into the music. all is not as it appears. that is what i've found out. urtexts become much more important in playing correct notes - giving interesting interpretations. coming closer to what the composer intended.
Topic: Piano Literature Syllabus