One of the stupidist set of questions in the PPL exams are those which seemingly require applicants to memorize the Safety Sense table. To my mind that is highly dangerous; never would a professional pilot try to remember the corrections for perf calculations for contaminated runway ops - they would assess the conditions, then look up the conversion factors from their documents.
Everyone should use the Safety Sense leaflet - and in the PPL exams the applicant should also be allowed to. I want to know that he/she can obtain the correct answer, not merely memorise a table.......