To understand your request, can you explain why you want to water the same station again over a short period of time? Why not aggregate it so that you water a longer period of time for the same station, as opposed to water it twice over a short period of time?
To conserve water. When you’re using spray heads with high precipitation rate, irrigating over dense soils (and/or on sloped lawns) you cannot have long run times — you get runoff and the water ends up on the sidewalk, driveway, or street. The solution is to break long runtimes into multiple shorter run times, with breaks in watering long enough to let the soil soak up the water (30 minutes is sufficient). This is a common irrigation technique.
Also, I made it pretty clear above that no matter how well the algorithm is designed, there always exist cases that some water cycles will have to be ignored.
In my opinion, and indeed this is just my opinion, it is simply bad practice for an irrigation controller to silently ignore/drop watering cycles, under any circumstances, but especially at the precise time when the watering algorithm determines the lawn needs more water. That is the kind of thing that kills lawns and frustrates users.
I do completely understand there are practical limits to what OpenSprinkler can do. But I think I’ve shown above that this ignoring of watering cycles can happen on fairly typical programming (i.e. simple zone repeats when Zimmerman method enabled and there’s an automated watering % increase). That’s not an extreme case at all. I don’t know the solution. It would be great if the least the controller could give the user a warning at the time the water schedule is programmed by the user letting the user know this will happen if watering percentage exceeds <x>%, or at least a warning (mobile app notification?) when actual watering % is increased to the point where cycles will be ignored on currently enabled programs. Or maybe constraining run times / repeat times so that it gives you a much more reasonable “worst case” to program for.
So I think it’s reasonable to require the the repeat cycles to be sufficiently far apart.
The only way to do this (to ensure ignoring cycles can’t happen) is to design and preview the watering schedule for 250% watering percentage. That’s a kludge. Besides, designing the watering schedule for 250% watering will result in suboptimal schedule at 100% (or less).
One solution is to set the stations to run in parallel mode
I don’t think that’s a solution because that requires even more tedious care with programming, in order to ensure I don’t end up with multiple zones firing at the same time, thus exceeding the electrical capability of the power-supply (not to mention insufficient water pressure with multiple zones activated).
I’ve highlighted the issue as best I can. Perhaps I do not explain the issue well, or my expectations are unrealistic, maybe both. For me, I will just disable Zimmerman method, adjust manually, and always preview my programs. Thanks for your time.