Opening an Issue to avoid this getting lost in commit comments.

bc5a97c#commitcomment-76875915

ci_random=TRUE can be very slow in some cases. I would argue that it would be better to set this argument to FALSE by default. If users need the additional information, they must take the active step of reading the docs and changing a flag. But at least, we won't take unsuspecting users by surprise with unacceptably long compute time using the default arguments.