I don't record those "future" actions in my action lists
If I've got some specific ideas about what needs to happen with a particular project (first this, then either that or that, etc.), I'll keep those notes at the "project" level, e.g. in project support documentation, and let the next action be my placeholder for day to day tasks. Once I complete a given "next action" sometimes the "next" next action becomes obvious and I'll record it (but not do it, unless it's less than two minutes and won't mess up my focus). If it's not obvious, who cares? I move on, knowing that when I'm reviewing my projects, I'll see the notes I had before, and when I'm in that "think about my stuff" mode, I'll make a concrete decision about what the next actions may be.
That's not to say that I never have more than one "next action" for a project, I just won't have sequential ones captured in the form of next actions. At risk of beating a dead horse, here's an example: say I need to email someone a request for a document, review the document and summarize it for a client. My next action would be "@email Joe re: document" which would probably spawn a "@wait Joe re: document" action. Once I get the document, obviously I'd "@review document from Joe" and after that "@computer summarize document" then "@email client x summary" or maybe "@agenda client x: summary" ... but I'd only have ONE of those actions in my next action lists at a time.
If I've done some big-time "project thinking" and there's a non-obvious flow of events, or some teeny dependency or checkpoint that I may forget, I might document that in the project support material ("have Sue validate summary for cultural appropriateness"), but for the most part, I trust my system enough to know that I'll revisit my project list when I have appropriate time to "think about my stuff."