If Brooks Koepka wins the first two majors of 2019… then he will have won four majors in a row. But… two of those majors will be the PGA Championship, as he won last year at Bellerive and would win in 2019 at Bethpage Black. So his four majors would be: U.S. Open, PGA, Masters, PGA. No British Open.
I contend that Tiger holds a Grand Slam because he:
Won and held all four major championship trophies.
Won all four in a row (i.e. there wasn't a year where they held one twice or something goofy).
Brooks wouldn't have done that - he'd be missing the British Open. So, while w