Just to be clear, it is advisable but not essential to use the word provisional. See Clarification 3.b/1Absolutely. Most people hit a ball that everyone assumes is a provisional - they might say so, or they might imply it by saying they're hitting another one or reloading or whatever. Even though it's against what the rule says (that you have to state 'provisional'), I think people now assume provisional because that's the case 95% of the time.
Once they've cracked the provisional down the centre they'll just tell everyone they're abandoning the first one anyway and that they don't want it looked for.