Pick one of the six different sailors, put it at the top of either set of rigging, and compare how well (or badly) he hornpipes his way down (a slight nudge may be needed to get him started).
I recently unearthed the version built by my late mother, Joyce, based on a design by Andreas Konkoly which appeared in June 1972 Meccano Magazine.
At exhibitions its behaviour was somewhat erratic - from time to time the poor sailor would either stick part way down or (more alarmingly) plummet from the top of the "rigging".
Joyce would usually attribute the misbehaviour to excessive mainbrace splicing by jolly Jack.
I naively assumed that a few quick adjustments to Joyce's version would be sufficient to get it to operate reliably - but it proved trickier than I expected.
As you can see I've tried half a dozen different ways of constructing the sailor (including one suggested in Konkoly's instructions as a simpler alternative). Some helped a bit - using Plastic Pulleys described by Konkoly rather than Brass used by Joyce seemed the most useful improvement as they reduce friction.
I experimented - fairly unsuccessfully - with tweaking the slope of the rigging and with rotating the nuts that hold the bolts in place to different orientations.Finally I realised the true cause of both plummets and sticking was the sailor landing on the fixing nuts, so I devised a way of fixing the bolts without visible nuts. Right Angle Road & Strip Connectors seemed a promising way to hold everything together, until I discovered that these are maybe the least consistently made of all Meccano parts - of all the specimens I own, only two have holes at correct ½" spacing - none of the rest would fit! Hence my choice of Collars holding the other side together.