Finally...?

Parrying isn't just "blowing it away"....I imagine you have seen judo flips, right? Where you use an opponents momentum against them and flip them over you...well parries CAN be strength based but it can also be agile and smooth, rolling their blade with yours, using it's momentum to turn it away or even against its wielder allowing you to insert your own deftly between their ribs...also swords on average do not weigh 30lbs...not even close...unless you look at the greatswords which even then barely even reach 10 lbs.

[color=#B000FF]Okay, in terms of a real parry, it is simply a shift in motion, causing it to go from forward to backwards, as you say.
And I know, I was exaggerating.
Great(and I mean GREAT) swords in the old days tend to be around ~14lbs at max. I was simply trying to make a point. In terms of if you're on the battle field, that sword may seem to weigh hundreds of pounds when you're in the heat of the moment.

Oh no doubt, I imagine when swinging a piece of forged steel for hours on end against what would probably seem like an endless wave...god I couldn't even imagine...I bet soldiers were riiiiipped...or would be if they had proper 2000+ Calorie diets lol.

Or get...SCURVY!