I think this topic will be a never ending post on this site, and others, until the end of time or the gurus teach otherwise.
I still feel that just getting your RE license isn't the be all, end all answer to someone who is intending on just wholesaling (assigning contracts). There is too much at stake, in my limited estimation, for a licensed person to be a wholesaler. I have read that a couple of people have been successful at just that. So, I guess it depends on you, as the wholesaler, what you want to invest in and how you want to protect that investment (time, money, blood, sweat and tears).
I believe that transparency and ethical behavior from the wholesaler is imperative. However, If you attend the closing, your seller and buyer close the deal based on the P&S contract you had with the seller, where does your fee (profit) come in? In most situations I've read about, most title companies and attys will have a problem with your role and being assigned a "fee". A double closing would be more appropriate and less "grey".
Having a buyer's list and employing that once you have a contract is not illegal if you flip to one of them. You should have a non-circumvent/non-disclosure with both parties in case they decide to boot you out of the transaction.
Assigning a contract is not illegal, but you'd BETTER read your state's laws to make sure you are not operating in a fashion that gets you fined, imprisoned and lose your business and assets. There are states that are cracking down on wholesalers and will persecute. But, those are few and far between.
Does it lessen a persons credibility just because they wrote some books, give seminars, write articles, give advice, or as an experienced person (real estate investor in this case) to question their integrity or bias? Whether or not they make billions, should that person not be giving advice? Especially if they are a lawyer? I don't like lawyers, but I have worked with a number of them. They are usually costly, don't know anything, but their respective niche, don't care about your troubles other than what it's going to cost them, and in the end, what are they getting out of the deal. I have yet to find an attorney who exhibits a different behavior. I know I might be generalizing, but that's been my experience.
For me, I have come to believe that you CANNOT do a wholesale deal, let alone any re deal, without putting up some of your own cash and taking some risks. You may not need to have good credit, but most deals don't require good credit. However, there are some lenders that do use your credit as a basis for the loan.
I say if you are upfront with the seller, put down some kind of collateral (money, EMD, Good Faith), have everything spelled out precisely and exacting in the contract, explain your intention (assign, or buy with the option to assign, or outright buy if not assigned or assignable), that is all you need to remain within the legal walls.
I AM NOT A LAWYER, CPA, DOCTOR OR EXPERT!