I kick open the door and charge into the room!

[Ridley's Cohort]

Uhhh... if everyone has a Ready Action for when the door is opened, then who's gonna open the door?

Someone will need to abandon their readied action to open the door, in which case the initiative of the other readiers (?) is lowered to that of the opener.

No offense intended, but you are not seeing the forest through the trees.

The guy opening the door is a minor detail. Some people is this discussion think he should get an initiative bonus. Others don't. Maybe the door takes one tenth of a second to swing open after it is kicked and he does get to ready his action before it is open. It doesn't really matter.

The real question is how do you decide who goes first when "everyone" is readied? The logical choice is to roll Initiative. Why invent new rules when we have a stat intended to address this exact question?

Assigning everyone the same initiative count seems more like avoiding the question rather than answering it.

 

[green slime]

Not everybody will ready an action: Some might delay, thus gaining a full rounds worth of actions...

Some may not even do that, but decide to cast spells, crawl up the chimney, hide, dispose of the evidence, or whatever else seems strategically correct at the moment.

Thus, the importance of the initiative roll once the two parties are aware of each other. NOT just when the door is broken down.