How do we ensure users read instructions?

As Jakob Nielsen demonstrated:

On the average Web page, users have time to read at most 28% of the words during an average visit; 20% is more likely.

For our business application, with users (call centre staff) whose job it is to use the software to carry out transactions on customer accounts, our testing has consistently shown that users don't read important messages.

For example, we have a transaction that makes a significant change to a customer's account. We want the user to read to the customer on the phone 3 bullet points (around 40 words) to ensure they understand the consequences of the transaction. The vast majority of users skip over that text and just try and click 'next'.

We have tried reducing copy as much as possible, and using visual prompts to highlight important text, but it hasn't made a measurable difference.

What can we do to encourage users to read important messages on a web page?