When "merge info sets" (the link sign) appears, separate info sets have automatic separate move names:
When these three information sets are merged (I used multiaction, not sure the same happens when info sets are merged by first clicking one and then the other), the move names of the last merged info set are used, which now wastes the previous automatically chosen letters a,b,c,d:
It is better to use the move names of the first merged info set, here a,b
When "merge info sets" (the link sign) appears, separate info sets have automatic separate move names: When these three information sets are merged (I used multiaction, not sure the same happens when info sets are merged by first clicking one and then the other), the move names of the last merged info set are used, which now wastes the previous automatically chosen letters a,b,c,d:
It is better to use the move names of the first merged info set, here a,b