> With unequal sized pulleys the ropes "slope" vertical
> component of the force in the ropes supports the load
> and the horizontal component is wasted by opposing
> an equal and opposite force in the matching rope on
> the other side

OK, gotcha, it's a vector thing. So for a vertical lift keep all
sections of the rope vertical. If I have to I can build up the
smaller one to 200mm or look around for a 200mm. Picked
these up at a scrap dealer for $5. 2nd-hand block down the
road was $130, so there's a pretty good "tinker" margin.
If I found another pair of $5 200mm pulleys I'd think myself
very lucky

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