Well, I know I can hit a lot harder and more effectively than most folk from strength as I'm much broader/heavier built than most people, and my 300+lb human-gorilla mate can KO most twerps with just a slap...he can throw me around like a pillow, lol.
We had a D&D arguement once...a friend, built like a chip (french fry to Americans, he weaighed about 100lb soakign wet) was arguing that it wasn't fair his 22 or so strength fighter,was getting out wrestled by a troll with 19 or so strength...to which I explained it was also MASS vs strength. He kept moaning, so our human-gorilla mate, picked him up, held him by one ankle and bounced his head of the floor.
"
SEE? MASS DOES COUNT!" he said.
lol
Most folk simply could NOT block attacks from my big pal. Nor could most lightly build folk stop hits from me. Skill though is an important factor, but very few folk are Steven Seagal!
Defence is a mix of armour and shields stopping blwos hurting you (damage reduction), dodging completely out of the way, moving so blows slide off harmlessly,and blocking the blow or redirectign its energy etc.
When something can hit REALLY hard, the ability to block or soak is reduced.
For example, an ordinary person trying to block a blow from a troll wil simply get his shield/weapon/arm smashed down and into himself.
I can see a semi-mystical monk being able to block such a blow though, it's heroic fantasy and I've seen some pretty amazing stuff done by true masters.
So, Strength should give a bonus to hit, imho