Changing Rule 40 isn’t the only way the rules committee can matter. They could come up with any number of other possible rules, which could lead to absolutely any outcome they want. For instance, if they want to rule out Trump, then they could say that the only people who can be nominated are those who have been endorsed by a certain number of sitting Senators, Representatives, and Governors. Or they could say that only people who have themselves held one of those offices can be nominated. Or, heck, if they really wanted to throw the party into chaos, they could say that only people with the first name “Raphael” can be nominated. Will they go that far? Almost certainly not… but they might still come up with subtler ways of keeping Trump out.
Doesn’t the rule about a candidate having to win 8 state contests in order to be eligible for the nomination prevent Kasich & Rubio’s delegates from actually voting for them? 
If that’s the case then and the rule isn’t changed then wouldn’t either Cruz or Trump have to get a majority on the 1st ballot?
I can see a variation on your prediction where, coming into the convention, no candidate has enough delegates to win on the first ballot, but Cruz clearly has enough to win on the second ballot. They could go breeze through the first ballot and then play the second ballot as close as possible to the usual pageant.
Delegates can abstain.
He’s not serious about losing. He just doesn’t want to win. What he does want is to continue to draw attention to himself, and that means being the kind of person he is. I find it orders of magnitude more likely he cares about getting fawning fans than actually being president. Becoming president means getting the most voters on your side even if they are just narrowly on your side, but Trump’s directed himself towards getting people to become huge fans of him at the expense of alienating most others.
:mad: Why don’t you ask him to renounce his religion, too?! sob Dammit, some things are essential to a man’s identity!
Naah, his religion is personal power. He’ll never give that up willingly.
After the first ballot,
And from another page on that site,
So, we do not know the actual rules of the convention. Those will be determined at its outset.
I was at a HS simulation of a Democratic Convention, which was held in the spring (during the school year). The nominee had not been established at that time, nor was there an obvious break-out leader, just one guy who was fairly well ahead. Our delegation was already pledged to a guy who was prettymuch dead-in-the-water. There was talk of our candidate throwing his delegates over to the ahead-guy, which as I recall obligated us to vote for him or abstain. I am not sure if the pledge rules work at all like that for the Rs. I do not think the Rs have been even close to a contested election in my lifetime plus another decade, so this sort of thing has not come up in a very long time.
Well, if you want to to be at the GOP Convention…
Its really quite simple…
Just click your heels three times and say,
“There’s No Speech like Foam…! There’s No Speech like Foam…!”
Cue Spoiler Box Special Effect
They’re OFF to Delegate Voting…!
(…whoever can generate Buzz…!)
To Hear with Ears the Spin that’s His
from noun to verb to declarative clause!
Oooooh, that other campaign is DEAD because…
because… because…
because… because…
because!
because!
because!
because!
BECAUSE…!
Because Of The SON-OF-A-BITCH He Was…!
They’re OFF to Delegate Voting…!
(…whoever can generate Buuuuuuuuuuuzz…!)
Hey, You! You’re Smiling! Stop That…!
Per rule 40(b), only the names of candidates who can present certificates from at least 8 delegations showing majority support in each of those 8 delegations can be placed into nomination and only these candidates can have nomination speeches.
Per Rule 16, any delegate who signs such a certificate for any candidate other than the one he/she is bound to vote for will be ignored. Any delegate who votes for someone other than the candidate they are bound to vote for will be ignored.
Per Rule 40(d), the chair of the convention will only announce vote totals for candidates who satisfied the requirements of Rule 40(b). The winner must get a majority of all delegates eligible to vote, even if their votes were not counted.
So, delegates can vote for Rubio or Kasich if they are required to, but their votes will be ignored.
There is no provision in the current rules for nominating additional candidates after the first round.
Those are the CURRENT rules. The rules can still be modified before the convention.
Classic. 
So how’s the Frau doing?
(Neeeeeeeigh!)
As the saying goes, “Once your reputation is done, you can live a life of fun.”
The bizarre advantage for Trump is that he has a lower threshold of politeness, manners, etc. to meet than the other candidates. Society demands less of him. So if Trump makes a concerted effort to improve his manners, attitude, speech, etc., he will get much more credit by the pundits and voters than if Cruz, Hillary, Bernie, etc. put similar effort into improving their image.