It helps but do not expect miracles. Even with sharing the trio details, very little activity triggers the computers that block the cards. A good idea is to have the collect call numbers saved on your cell phone and Skype. It could be part of your daily routine to end your day unblocking your cards. 
I always use an ATM card to withdraw local currency from an ATM in Europe. I usually end up getting a good exchange rate with minimal fees. I really don’t like to exchange currency at banks because they love that business and mark it up and give you a lousy exchange rate which more than makes up for any fees they don’t explicitly charge you. Also don’t like to travel with large amounts of currency, although I will withdraw a decent amount to try to minimize trips to the ATM. The only problem I remember having was being unable to read the instructions on the ATM!
Due to the 3% fx fee, and I didn’t want to get a new credit card just for the trip, I didn’t use credit card very much. I got burned when I purchased an airplane ticket in the U.S, denominated in dollars from British Airways using the BA website. My credit card company charged me the 3% fx fee!!!
Also, a long time ago, while living in Japan I had a funny experience. Was trying to withdraw about $400 but the Japanese ATM has a “10k” button, so you enter a number plus the 10k button. I ended up withdrawing equivalent of $4,000 by mistake.