Well, I suppose its up to your group/GM to make the call on what's possible. If you did some stuff in preparation for a known confrontation, you could define that as one scene. That said, here is what I found on the subject in the rules:
Maneuvers result from an action and create temporary aspects that you can free-tag 'almost immediately' (at most within a scene)
Declarations don't require an action (take no time) and create a potentially persistant aspects that you can free-tag 'almost immediately' (at most within a scene)
Assessments generally take larger amounts of time, but create a potentially persistant aspect that you can free-tag possibly much later (even several scenes later)
With respect to Rick's "power-up montage", I'm not sure. It may be that the rules were tightened up a bit since he previewed them. Or it may just be a matter of terminology shifting. For example, it might be possible to call most of those steps he suggested a form of Assessment, rather than a Maneuver. They meet the 'preparation time' requirement for Assessments, but differ in that they are an attempt to create an aspect, rather than discover an existing aspect. The scouting and research examples (the last two) sound very much like Assessment.
I like the examples given; they sound flavorful. At the same time, I am (as always) concerned about the potential for abuse, as the players say they spend an hour after breakfast every morning prepping 60 assorted free aspects for later use, thus ensuring that he can spend three or four every roll for the rest of the day.
Perhaps the answer lies in creative interpretation of the durations. Have each maneuver-based aspect last until the maneuver is 'spoiled' some how. A good example of this is in the rules describing aspects involving aiming -- the aspect only lasts until something causes your aim to falter (like the target moving into cover). Aspects involving magical focus (purification rituals, building up charges in charms, etc) might only last until you are involved in a scene in which magic is being flung around. They last for that scene, but then disipate if not used, because their energy was disrupted by the magic flying around. Aspects involving concentration or centering might only last until something stressful occurs to unsettle you. And so on.
And in any case, if players start writing down more than a few such aspects, I'd probably think hard about a mechanic to limit them in some way. Perhaps no more than one aspect per relavant skill, or no more than X, where X is the highest of the skills being used to justify aspects.
For example, 'Magic