I recently came across this page, http://ivantic.apnoia.org/fizika/faq/hot_water.html which seems to make some sense. I personally don’t have much vested in the answer, having the reams of time as I do to just shove an ice-tray in the freezer and forget about it, but for people with more pressing schedules that need to know whether they can make ice quicker with boiling water, there is hope. Because I guess nobody really needs it that badly that they’d just try it anyway?