Well, spanish ATCs were working on 5-1 basis just 3 years ago, and 6 shifts on that 5 days of work sometimes. Some people worked 29 shifts in one month. And always remember that the day "off" was the sleeping day, we had night the last day, so indeed we had 24 hours off!
Single European Sky to make routes shorter... nice idea! Like if Lisbon ATCs didnīt call us usually to ask "is Talavera area active to send a direct?". Or if like LFBB didnīt have militar areas close to the border and was able to acept directs sometimes... the main problem are not the number of ACCs, but the militar areas.