Really good question. Not really sure the irreparable harm “acknowledgement” in a kid’s contract holds up in cases of a poorly informed or misled kid. The differential in knowledge and bargaining power is quite inequitable if the kid is unrepresented. But who’s going to spend the money to litigate the issue for a marginal player? So, schools like Duke clearly have the better side of the argument to stop transfers like Mensah from playing at Miami. But schools like Duke also IMHO have the much weaker side of the argument for big monetary damages based on a contract breach, because of the phony nature of NIL contracts. Duke might have argued that it would experience a big loss of revenue if Mensah didn’t play at Duke, but the same “speculative” damages/proof issue would be there, especially given the 13th Amendment’s proscription against enforced peonage. I think in the current state of affairs, lawsuits for injunctive relief for broken revenue-sharing/NIL will result (1) in negotiated big dollar buyouts for the best players and (2) players returning to their original schools when there isn’t a big money buyout on the other side.
To answer your question, I do think the “irreparable harm” acknowledgement in standard contracts will keep all but the most valuable/marketable players from attempting to breach their contracts. Why buy yourself a lawsuit that could instantly get a TRO slapped on you and your destination school (since you have already undermined your position by agreeing that irreparable harm exists) unless the destination school is a deep pocket ready, willing and able to buy an expensive release from your contract?
Suggestion: If the courts are going to enforce contractual acknowledgments of irreparable harm given by ignorant young men (perhaps with sleazy agents) who haven’t a clue what they’ve agreed to, why not go to the next logical contract step and include a high (but not unreasonable) liquidated damages clause in these contracts? If Mensah breaks the contract to go to another school in the same conference, he agrees that Duke will have suffered damages of at least, say, $2.5M ($1.5M to another conference). A facially-reasonable liquidated damages clause such as this would save the jilted school from the charade of suing for a TRO in order to squeeze some dollars out of the transition. Why not just monetize the damages up front?
This whole thing is such a soap opera, but it is rationalizing itself—at least in terms of the financial side of the transaction—as we watch.