Hard.
Blow gently? Pfft. You ponce.
That's not going to do anything.
He can try it gently and gradually work his way up until it works, if he doesn't have balls.
Well if he has a lot of pressure built up in his head and blew really hard it feel like someone set iff a bomb in his ears.
One time my ears didn't equalize the whole flight and when we landed it felt like an elephant was trying to crush my head. I thought if I blew hard the pain would end quickly, WRONG, it hurt so much I fell and almost broke my laptop. Even then it wouldn't equalize, so throughout the whole day my ears would pop and each time it felt like hell.
But that was the only time it hurt now that I think about it... So maybe you're right.