I really don’t like similar cards coming up on the same day; so if I have (say) 7 new sentence cards for the same vocabulary word to be learnt, I’ll give them all an interval of 1, and then ‘space them out’ in time.
Let’s say I’d want just one of those cards per week, first I’d do a 1!, then a 1-43 (without !).
Problem is, as the command says of course, it’s RANDOM; so if I’m out of luck, 2 (or more) of those cards might still be assigned the same due date … 
So, could there be a fourth option:
x-y˘ = x-y days, evenly spaced in time
Happy learning 
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