Jecht's view of strength was flawed, not his parenting tactic (no less disagreeable, nonetheless). In order to make Tidus successful in his eyes, he had to motivate Tidus, by putting him down, so that Tidus would feel threatened by his inferiority, and aim to surpass his father. This tactic almost works, and Tidus is almost able to surpass his father (if he has not already done so); however, it also has the unfortunate side effect of making Tidus hate Jecht.

Though the best way to help someone occasionally requires that you hurt them (when parents yell at you for coming home late, it's out of love and concern, not hatred, as many people seem to think), Jecht clearly crosses the line into needless pain.

The game also mentions that Jecht was usually drunk, also. In one of his spheres, it mentions that he will quit drinking after attacking the Shoopuf. In another storyline scene, Tidus challenges his father after being scolded. He tells him "stop drinking, then, if you're so great." To this, Jecht responds "why do today what can wait for tomorrow." He's usually too drunk to develop a sensible concern.

Whether or not they have had sex with more women is up to debate. Manly men, they are.