Re: Why strip strike?
As others have said, a strip strike with the rod pointed directly at the fly puts all the force directly into the hook quickly (less line and tippet stretch).
But for some species, like bonefish, there is a downside, especially for those new to it, so I tell my friends who fish for bonefish to forget the strip strike. The problem, especially with downtown fish that have all been caught before, it that their reaction to feeling the hook is explosive, and they will often pop the tippet before the strip strike is halfway through. The angler cannot release the line fast ennough.
With a rod strike, anglers seem to have just enough time to react and doens't break them off immediately nearly as often. And the smaller hooks do not require the pressure to set as larger hooks and bonier jawed prey.
When using tiny little strips with a crab fly, don't get a death grip on the line, and when he picks up, do a "slip" strike, not a "strip" strike. Once your line is clear and your drag is screaming, you can always safely do another strike against the drag with the rod.
More bones (large ones) are lost from broken tippets in the first second after the bite than in the entire rest of the fight, until it's time to grab them to get the fly back.