It was widely reported in yesterday's news that one of President Trump's impeachment lawyers covered his head with his hand and recited a bracha every time he took a sip from his water bottle. It has always been my understanding that once you have recited Shehakol once you do not need to keep reciting it for each sip. Perhaps I have been doing it wrong all these years? Of course, after a sufficiently long interval of time the action you are no longer "covered", so to speak. What criteria determine how frequently one must recite Shehakol when drinking?