P&O Change Dress Code. Good or Bad ?

From March 20th to May 5th 2016 P & O have decided to simplify the dress code on Adonia, Arcadia, Aurora and Oriana. This will bring these ships in line with the rest of the fleet.

They will have Black Tie Nights and Evening Casual. P & O hope this will help guests with the problem of what to pack but will allow the combination of formal to being totally chilled.
Black Tie will create a special atmosphere adding glamour and elegance to the evening. I must say to see an entire ship dressed to the nines is quite a spectacular sight to see.
Evening casual will mean that guest will not need to spend ages getting ready and will have more time to enjoy the on board activities. I hope this is not a green light for standards to slip. No one wants to see shorts and vest tops at dinner.
Let me know your thoughts ?