DH and I were just on the Dream last week. We splurged for Concierge and took advantage of the MDR Room Service in our suite. We asked the wonderful CM who gave us an amazing private dining experience which way was best to tip--to our onboard account or in cash. He probably wasn't supposed to share this information with us, so I will leave his name out of this post, but he told us that if we tip in cash, he can keep it, but if we added the tip to our onboard account, it would be split between the CMs (not sure how many or what pot it would be added to, we didn't ask). Anyway, with that knowledge, we gave him cash.
I didn't ask if he could keep the cash because he just didn't have to tell anyone he received a tip or if that was their actual policy, but I didn't really care. I know many waiters and waitresses who don't claim all of their cash tips, so I wasn't worried about it.
Anyway, with this knowledge, we've decided to tip in cash on the ship going forward. Just thought I'd share our personal experience.
Oh, and we tip $10pp in Palo for both brunch and dinner--we always have the same server for both, so we just try to be consistent. Plus, DH doesn't drink anything bubbly, and the server always lets me have his mimosa at brunch!
We've only been to Remy once, and we tipped $50, I think, on top of the auto gratuity for the wine. We had a bottle + 2 glasses of wine, so with that, we probably tipped a total of $75.