I strongly believe that it depends on the situation, the country, the need for it to work and the logic (behind the systems).
However, no matter what the place or situation is if the people need the system to work then they will make it work especially if they have peoples lives at risk. The decision would fall upon those in charge and it they were to fail, all else would with it.
If the government were to put in place two different 'systems' in place then it had to of been though through because the people of the country depend on them to make it work. The government or the people in charge wouldn't be doing their jobs right if they made a decision on impulse and 'in the moment'. Also, I don't believe that they would of put in place a new system without thoroughly thinking it through and all deciding on it. The people are in charge are there for a reason and as soon as they make mistakes-no matter how small- they will be the ones who are judged,hated and maybe even demoted.
The Hong Kong and China crisis is an clear example of how when the people in charge fail and cause conflict everyone else sufers and people aren't happy with them. Resulting in riots and violence uprising, like IO said before because they haven't made the /system' work they are hated and called upon to be demoted and maybe fired. When we rely on the ones in charge to much, it can fail and we are left with uncontrollable arguments and demands that can't be met.
Therefore, I believe that if the situation is so desperate they will make it work, because they have to and if the don't try hard enough to make it work it will result in a terrible situation that was worse then just using one system. People disagreeing with the two systems can cause a major issue as show by the Hong Kong and China crisis. If they had just acted maturely maybe they wouldn't be in the situation that they are in now.