Check out the resource linked above, which is an explanation of each program component from the ISU. I just keep seeing so many comments about how this or what technical mistake should contribute to the significant dropping of one of the areas of PCS, but I really believe these assumptions come from people creating their own definitions of what the criteria mean.
For example, the skating skill mark does not have some formula that states that you take the total amount of time a skater remains on his/her feet in the program, divided by the total length of the program, and then you assign that percentage as the skating skill for that skater. Sound funny? Read some of the comments across the internet!