I am not sure where you are looking when you say "Princess stated policy". I have looked at my documents, the website, and their brouchure and there is no formal policy that I could find. On their website they do make suggestions but it does not show that this is their formal policy (see below). As I have stated to you before I believe that todays cruiselines understand that some(not all) people do not want to get dressed up on these nights. Unless you are traveling on the QE2, Silverseas, or other cruiselines that charge '$3900 for an inside cabin. That is why Princess has decided to use the Horizon Court for a Bistro at night and whre they serve in a more casual atmosphere. That is the beauty of "Grand Class Cruising" according to Princess you can do what you want when you want. If it is stated in their Newletter on how to dress for the evening, that is not policy. That is a suggestion on what to wear for the evening.
Believe me, I don't mind getting dressed up. It gives the ship a beautiful atmosphere. I do beleive in freedom of choice and if this is how some people want to be well, it should not spoil your evening. REMEMBER: You don't have socialize with everyone. What there should be is a dress code enforced at the pool area for people who wear bathing suits that are too small or just do not fit the body properly. But hey, that would be a perfect society.
Once again I would like to wish everyone a safe trip,
You should dress for cruising the same way you would dress for any smart land-based resort. Casual sportswear including shorts, light-weight pants and jogging suits, is the order of the day both at sea and ashore in our hotter climates. Just remember to bring a light sweater or jacket for cool evenings. For shore excursions, bring a sweater, a light jacket, and an all-weather coat, depending on your destination. Due to unpredictable weather, don't forget a hat or visor, and a collapsible umbrella.
You'll also want low-heeled, rubber-soled shoes for strolling on deck as well as comfortable walking shoes or sandals to wear while exploring.
When you're in port, evening dress is casual, slacks, sweaters, blouses, open-neck shirts, etc. are typically worn. Shorts, cut-off T-shirts, "torn" jeans and bare feet are not permitted in the dining room. For semi-formal evenings, passengers dress as they would for a fine restaurant at home, with ladies in skirts/dresses/ pantsuits and gentlemen wearing a sportscoat or suit. Tuxedo rental can be arranged prior to the cruise on certain itineraries. On formal nights, ladies prefer evening gowns or cocktail dresses and men turn out in tuxedos, dinner jackets, or dark suits. See the chart below for general dress code schedule.
Length Of Cruise # Of Evenings Casual # Of Evenings Semi-Formal # Of Evenings Formal
7 days 4 1 2
10 days 4 - 6 3 - 4 2
11 days 5 - 7 4 - 5 2
13 days 6 - 7 4 - 5 2
14 days 5 - 8 5 - 6 3
15 days 5 - 8 6 - 7 3
16 days 7 - 8 6 - 7 3
19 days 8 - 9 7 - 8 4
21 days 10 - 12 7 - 8 4
23 days 10 - 12 7 - 8 4