Infield Fly Enforcement

[Lapopez]

[This was touched upon in the dropped third strike thread but I didn't want to drift too far off.]

In that thread SanDiegoSteve said:

Originally Posted by SanDiegoSteve

I agree 100% that both offense and defense are responsible for knowing the situation, but a strong verbal announcement of an Infield Fly is vital, especially involving borderline situations, as the IF rule is subject to umpire judgment, unlike the uncaught third strike rule, which is cut and dried.

I'd say going back at least 8 years this concept has bothered me. Is it still the IF mechanic to enforce it even if the umpires mistakenly do not announce it?