The writing displays Beethoven's characteristic disregard for the performer, and is in several places both technically and physically exacting, with many sudden changes of dynamic, metre and tempo. This is consistent throughout, starting with the opening Kyrie where the syllables "Ky-ri" are delivered either "forte" or with sforzando, but the final "e" is piano. As noted above, the reprise of the "Et vitam venturi" fugue is particularly taxing, being both subtly different from the previous statements of the theme and counter-theme, and delivered at around twice the speed. The orchestral parts also include many demanding sections, including the violin solo in the "Sanctus" and some of the most demanding work in the repertoire for bassoon and contrabassoon.