Have you ever tried shaking hands with a man that doesn't grip?
It's like holding wet lettuce.
Shaking hands with a lady, one should grip and support her hand, but not squeeze, but be reassuringly firm. Imagine how you would cuddle her on a cold winter's night, strong yet still tender.
If a bloke does the 'World's Strongest Man' grip on you, wince and cry out in pain then, as he momentarily releases his grip, push into the web of his hand and squeeze, whilst turning your hand on top of his, so yours is uppermost. It's pure dog psychology, but it works.