Hitsounds are supposed to give feedback. Having a single hitsound during a slider is missing the purpose of hitsounding because it gives the player a feedback that they hit something, while they didn't.
Sliderticks are an edge case: The player isn't pressing down or releasing a button at that very moment, but the slidertick is atleast visible and expected to give some kind of feedback (even though slider ticks normally give rather unrecognizable or almost silent feedback - that's why slidertick hitsounds should be used rarely and should have a lower volume than regular hitsounds in most cases).
If a mapper really feels the need to hitsound a sound during a slider (which I personally would never do, why would you hitsound to a rhythm you are not following - oh well) they should atleast increase their slider tick rate to a point that covers those hitsound-worthy beats, in order to use slidertick hitsounding.
I have seen one acceptable use of sliderslide hitsounding so far - fanzhen has used it in a marathon (i don't remember which one) to play a rather calm hitsound on every 1/8-beat of a longer slider, to follow a special instrument with it. Yet this case is so rare that the rule should stay as it is.
Sliderticks are an edge case: The player isn't pressing down or releasing a button at that very moment, but the slidertick is atleast visible and expected to give some kind of feedback (even though slider ticks normally give rather unrecognizable or almost silent feedback - that's why slidertick hitsounds should be used rarely and should have a lower volume than regular hitsounds in most cases).
If a mapper really feels the need to hitsound a sound during a slider (which I personally would never do, why would you hitsound to a rhythm you are not following - oh well) they should atleast increase their slider tick rate to a point that covers those hitsound-worthy beats, in order to use slidertick hitsounding.
I have seen one acceptable use of sliderslide hitsounding so far - fanzhen has used it in a marathon (i don't remember which one) to play a rather calm hitsound on every 1/8-beat of a longer slider, to follow a special instrument with it. Yet this case is so rare that the rule should stay as it is.