Read Mebane Faber's and Gary Antonnacci's white papers and come up with your own conclusions. Then if you have questions post them here. Trying to convince you is the wrong angle IMO. You need to have your own conviction rather than someone else's.
The problem arises when this strategy, just like any other, goes through a time of suck. If you don't have your own conviction then you'll give up on it, even though the performance was consistent with the past. That's why strategies like momentum and value investing work over the long run, they go through enough sucky periods that everyone abandons them. It keeps the strat from becoming overcrowded and unprofitable.
Tom Basso was featured in The New Market Wizards book and what he would do is lock himself in a room and go through a backtest line by line, trade by trade. He would look at it and say to himself 'did the strategy perform like I would have expected it to? Could I see myself taking this trade in real life if my system told me to do it?' He wanted to know and understand his systems at this level of detail so he would have the conviction and confidence to trade it in real time.
I trade a system very similar to the Ivy momentum system but I've spend thousands of hours researching and back testing it so I have confidence in what I'm doing. I would suggest you engross yourself in it before ever seriously considering trading it in a live environment.