1)  Finding the rhythm helps you pronounce the words

-     /    -                        /     -    

gen- tle -er. rather than gent-ler

2) Finding the rhythm gives you a sense of the character's energy

Knowing the iambic meter, you can feel Emilia's energy change between her first line and second.

In the first, it's drawn out (six iambs!) and seems relaxed.

Emilia

How goes it now? He looks gentler than he did.

Compare that to the way her energy sharpens in her second line, her response to Desdemona's line.

Desdemona

And bid me to dismiss you. 3.5

Emilia

/ - /

Dismiss me? 1.5

She stresses Dis in a way that doesn't reflect the normal pronounciation of the word; it feels like she is jumping in on what Desdemona has said.

When the rhythm is varied or feels "off" in this way, it can signal that something is happening:  confusion? agitation?   The actor has to play with it to figure it out.

Now let’s look at the Rhythm between Character’s lines…