But he had them laughing out loud on Sunday and cheering a team selection in the best traditions of the squads of yesteryear known as the Busby Babes and Fergie's Fledglings.
The normally austere Dutchman's comic moment came as he attempted to demonstrate how Ander Herrera had been fouled by throwing himself to the ground in front of an astonished fourth official.
The crowd loved it, although Van Gaal felt obliged to apologise.
“My emotion was a little bit too high,” he told Sky Sports, “So I apologised to the ref and linesman and fourth official.”
One of the many criticisms of the veteran coach has been that he has failed to understand treasured United traditions, including adventurous attacking football and the promotion of home-grown players.
It has been the lack of excitement, as much as underwhelming results, that have caused speculation that Van Gaal will lose his job at the end of the season, despite having a contract until 2017.
Sunday's team selection may have been largely out of necessity with a dozen senior players unavailable but the Dutchman threw three youngsters in for league debuts against title challengers Arsenal.
He reaped rewards when 18-year-old Marcus Rashford scored twice and added an assist in the 3-2 win, a return that gave the Manchester-born striker four goals in four days.
Tim Fosu-Mensah, 18, and James Weir, 20, were brought on as substitutes and with Adnan Januzaj, 21, Memphis Depay, 22, and Jesse Lingard, 23, all involved, United fans saw a glimpse of a brighter future for the first time since Alex Ferguson retired three years ago.
As England international Michael Carrick said, a third win in seven days, with 11 goals scored, has given the side new confidence going into games against Watford and West Bromwich Albion.
United are also through to a home FA Cup quarter-final against West Ham United and play arch-rivals Liverpool in the last 16 of the Europa League.
But will it be enough to save Van Gaal?
British media have reported that United have been in touch with Jose Mourinho's representatives about succeeding him.
The Sunday Times said the United board were split over appointing Mourinho, adding that it wants to put a director of football in place for the first time.
While it seems highly unlikely that Van Gaal's squad can make up a 12-point gap to win the Premier League, they are only three points behind Manchester City in the chase for a Champions League place, which could also be achieved by winning the Europa League.
Should United finish the campaign with a trophy and Van Gaal is still be in charge next August, he might look back at a Sunday in late February when Old Trafford warmed to him as a turning-point.
Original source: Man United has Louis floored