I've booked a 10 night Western Med cruise and the time allowed at some of the most desired locations seems woefully short. Once we exclude bus or train travel times at Livorno and Civitavecchia we probably only have 9-10 hours in each city (Firenze and Rome). So a radical plan has been proposed: Don't reboard the ship at the harbour; but take a high speed train intercity.
Pros:
Get to Rome during the evening and have time to visit more sights.
Be available to start the museums when they open in the morning.
Save time in traffic.
Take part in the evening passeggiata.
See the buildings floodlit at night.
Cons
Extra cost for train and hotel stay.
Dinner and breakfast at own cost.
Missing out extra calories in the MDR (or is this actually a Pro?)
From our perspective, after such a long period of non-travel, time is money, so the additional costs above definitely seem work the added time in the Eternal City.
Provided I prewarn guest services of my plan so they aren't tempted to delay departure at Livorno and send out a search party, are then any other factors or risks I need to take into account? Is this a mad plan or worthwhile undertaking?