The heroes, in the original WWH, did not job, they were outmatched by the Hulk's power in every way imaginable. He was angrier and stronger/powerful than ever before, and yet still managed to hold back his power throughout the entire event. That's why he smashed and pummeled his way through the heroes as if they were tissue paper.
Only Zom-Strange and a fully unleashed Sentry were able to fight him blow for blow, and even then (as mentioned and proven in Incredible Hulks #634) the Hulk was holding back.
Not only that The Hulk was not at Worldbreaker levels when he defeated Zom-Strange and the Sentry.