Your current rating is too far below your peak to join this tournament

Since it is still in effect and they've had plenty of time to "correct" it, simultaneous games cannot be "against the site rules." Their programmers would have to be some of the least competent professionals on the planet. Given the quality of the site, that is not the case and they have chosen to leave it as it is for the time being.

The link has this: "And how do you accumulate trophies to advance? By playing, and by playing well! All that matters is how many rated wins and draws you score against random challengers."

And Martin said Simuls are supposed to be unrated, which I admit I did not verify.  So I looked it up and found this:

https://www.chess.com/article/view/chess-simuls

Which has this: 

The above parts in bold should be customized according to the desired parameters. Here are the available options:

• game = chess, chess960, crazyhouse, threecheck, or kingofthehill
• rated = rated or unrated

So I guess when Martin said "officially" he meant in the federations, and not necessarily on chess.com. I take back my comment about you wanting to circumvent the rules, and apologize for not having put the due diligence in to look it up myself before doing so.

They are actively working in a solution to stop awarding trophies for simultaneous games. Code changes have to be designed and tested to make sure  they don't break other things.

They certainly haven't decided to leave it as it is.

The content team has always meant for simuls to be unrated, but my guess is that when implementing the options, the leveraged existing challenge mechanisms to do it.

That said, most people dong it have sent significant staying decreases and that in itself is something that is an issue. It probably wouldn't be too off base to also implement the same limit on rating decreases to event entry on trophy accumulation. 

So are we looking at a change in the rules pretty much asap or are they waiting until a new division starts?

Or are they thinking more like after the first champions league?

My understanding is as soon as possible.

Rules were updated:

https://www.chess.com/leagues

Thank you Martin! I much prefer this to be honest.

This is just good news.

What kind of tournaments are you trying? Blitz? rapid? What is the message you get when trying?