What exactly is iambic pentameter?
Yes it does have to stick to a particular rhythm to be exact iambic pentameter. Most of Shakespeares sonnets adhere to it strictly. But in character work, having strict adherence is dull at best. Throughout his development Bill finds new and different and effective ways of irregulating the ten syllable line to fit the mood, passion, situation and assuredness of his characters. Increasingly he turns to blank (unrymed) verse, and then to prose. As a for instance look at the development in both Midsummer and Much Ado. In the first he sticks to a rigid aimbic form to begin with, but as the play develops and his characters become increasingly uninhibited their verse becomes equally free, until it culminates in Bottoms wonderful dream speech when he wakes. Then, at the end of the play we get the mechanicals playing in very stilted rhyme and rhythm, just to show us what a bad play consists of. And yet well played there are moments even in the Pyramus and Thisbe doggerel that can (and I believ