Rudy does not have a point because pimike asked about transferring funds from one book to another. So he has a book already funded. In this case, he can transfer the funds from Book A to a private wallet *which requires no KYC* and then transfer it from the wallet to book B. End of story.
Why do people find this so complicated that they insist on wanting to do it directly from Book A to Book B? You can install dozens of free wallets on your desktop or your phone. Again, no KYC. The one downside? One more BTC fee, which at the moment is 50cents.
So, you want to know what the problem is with skipping this intermediate step? Countless things can go wrong.
1. Some books like 5D/BAS freeroll you on BTC fluctuations. If Book B is BAS, and you enter that you want to deposit $1000, it will calculate how much BTC you need to send. Now you request the payout from Book A. The longer that Book A takes to pay, the greater the amount that BAS will freeroll you on BTC fluctuations. If BTC goes up in value, they'll ONLY credit you with the $1000. If BTC falls by 50% in value though, they'll credit you with $500. In other words, you want to get the deposit in ASAP. The amount that BAS will freeroll you is huge in comparison to the BTC fee even on small BTC fluctuations.
2. Suppose you use a promo code for a bonus at Book B. Then Book A cancels your payout because of KYC or something, causing a long delay. The promo code may now have expired and if you try to use the promo code again, you will not get the bonus.
3. If at Book B it generates a BTC address for you but then the deposit comes in over 24 hrs later, it can take a long time to get credited as they sweep 'old' addresses less frequently.
I could come up with 10 more. Will going from Book A to Book B work for the most part? Sure. But why complicate your life for no reason?