> In practise, therefore, trying to optimise all parts of a program means doing a so-so job on all parts of a programme. This reads as if the author had sudden

> In practise, therefore, trying to optimise all parts of a program means doing a so-so job on all parts of a programme. This reads as if the author had suddenly remembered he's British halfway through the sentence. Quite jarring. (Not to mention that 'practise' is a verb.)