I dislike any programming rule which includes a number.
The issue is whether sections of similar code implement the same idea or just happen to be accidentally similar. The number of instances does not really matter. If you have 100 lines of code which are almost the same two places in the program, then you should unify sooner rather than later, before they are allowed to diverge.
The issue is whether sections of similar code implement the same idea or just happen to be accidentally similar. The number of instances does not really matter. If you have 100 lines of code which are almost the same two places in the program, then you should unify sooner rather than later, before they are allowed to diverge.