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surefire plan is the most popular phrase on the web.

fail-safe plan 111,400 results on the web	surefire plan 119,500 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
IT WAS MY FAIL safe plan to reveal your entire sick sordid past will kick in. SAFE PLAN"? Remember, Pryce, if I die, my fail WHAT THE HELL DOES THAT MEAN, "FAIL SAFE PLAN.	It's a surefire plan, Alex. I've worked out a surefire plan that will get me to the top.

fail-safe plan

111,400 results on the web

surefire plan

119,500 results on the web

More popular!