I certainly don't mean to tell anyone how or what to tip but for the record Disney specifically states that Palo's tip is included. Knowing this we do still leave a modest tip.
From the Disney web site........................
http://disneycruise.disney.go.com/dcl/en_US/help/overview?name=OnboardServicesFAQLandingPage#9
It is customary to give gratuities in recognition of service, which you will most likely be treated to in abundance aboard the ship. As a guideline, may we suggest the following:
Per Guest per cruise 3-Night 4-Night 7-Night
Dining Room Server $11.00 $14.75 $25.75
Dining Room Asst. Server $8.00 $10.75 $18.75
Dining Room Head Server $2.75 $3.75 $6.50
Stateroom Host/Hostess $10.75 $14.50 $25.25
Dining Manager Your Discretion
Room Service Your Discretion
Palo Gratuity included
Vista Spa & Salon Your Discretion
Babysitting Gratuity not expected
Shore Excursions Optional; not included in shore excursion price.
For your convenience, a 15% gratuity is automatically added to bar, beverage, wine and deck service tabs. All gratuities can be charged to your room charge.
At the Walt Disney World® Resort, 15% is the customary gratuity at restaurants and bars.