As i have observed them, even if they're, at a certain moment, very prone to cross this can change and the "very likely" crossing turns out to _not_ happen.
I've observed same; that's why I usually wait for another candle afterward to confirm the cross.
And I also do not use the numbers suggested by Goomboo. Sometimes I even change the timeframe I'm looking at (other than just hourly all the time), depending on other factors. But overall I have to say, the simplicity elucidated by Goomboo's system has instilled a confidence in myself to develop my own personal trading system, and to stick with the game, and I find that as long as I stick to my system (really just A system, no matter how simple/complex), I keep profiting more than I would just buying (or mining) & holding.
There is definite value in OP here and I certainly appreciate it.