Slider anchors/nodes must not be used to manipulate slider speeds (whether they are normal nodes or red ones). Using extra nodes to make a slider "wiggle" is usually fine, but using so many that the slider gets scrunched up (which also makes the sliderball go crazy) or become a "hold slider" is abuse of the hitobject's intended use and is not allowed. AIMod (shortcut ctrl+shift+a) will also point out sliders that move in an "abnormal" way, so make sure to check that if you're unsure of a slider.
This rule is confusing to me. What is its purpose? Are we banning/limiting the use of crumpled sliders in any way?
I do not have a suggestion yet to clarify this rule, so please discuss. If it would help, give me an example of an unrankable slider according to this rule.