Note that the freeze at the bottom of the ladder is mandatory, but the next freeze at the top of the same ladder is dependent upon Jumpman's vertical position. (Jump!)
Dean it seems like most people move to the sides of the board and attempt to go around a freezer guarding the middle ladder on rivets. Is the vertical position of jumpman the only trigger to break the up and down the ladder cycle? Just exiting the area near the ladder seems to break the cycle but I may be mistaken since I try to climb the ladders on the sides and am unsure of when the cycle actually breaks.
Yeah, this is the most common situation where you can really see the whole cycle (and where it can be the most annoying). Another common spot to see it (and potentially take advantage of it) is on the left side inner ladder next to the oil can on the pie factory.
So, on the rivets, if you see a wandering fireball on the middle platform where the top hammer is located freeze on the left half of the platform, then:
IF you are currently BELOW the vertical position of that platform, the fireball will unfreeze and move to the right until it sees the downward middle ladder under the hammer and it will climb down this ladder and it will always freeze at the bottom of the ladder. When it unfreezes it will always immediately climb back up this middle ladder. When it gets to the top, then:
IF you are currently BELOW OR EQUAL TO the vertical position of that platform, the fireball will freeze again at the top of this ladder, right under the hammer.
So, as I hinted to Chris, if you are standing on this platform (or the same level platforms on the right or left sides of the potentially unplugged rivets) and you want to avoid this second freeze, all you have to do is jump as the fireball reaches the top of the ladder so that its vertical position check fails and it will just move left (as all fireballs always do) instead of freezing.
Also, once this cycle plays out and the fireball moves left from the top of the ladder, it doesn't necessarily repeat. At this point the fireball goes back into a roaming mode for a variable amount of time before going back into the freeze mode. while roaming it could easily wander off to the right of that ladder or it could climb up or down any nearby ladder, etc.
Oh, by the way, back to the pie factory situation -- you can take advantage of this cycle in the opposite way here. When you climb up the outer ladder to the top conveyor and you know that a freezer which was just frozen at the bottom of the inner ladder is now climbing to the top of that same inner ladder . . . simply stand still on the conveyor until the fireball gets to the top and it will freeze -- buying you more time to complete the screen. It's counter-intuitive, since you will often have a chance to climb up onto the adjustable ladder or jump over a pie at this moment -- resist doing this! If a pie is coming, just stand there and drift back towards the fireball, knowing that you are forcing it to freeze, THEN jump over the pie and finish the screen.
Anyway, there are a bunch of little ways like this to manipulate situations that involve freezer bahavior to your advantage once you become confident that you really know what they are going to do.