Whether or not you disagree with it's concept is irrelevant as it's very much an actual measure, but maybe you just misunderstand it? I also think you've completely misunderstood my point, maybe I wasn't clear or maybe you're not getting it, either way it doesn't matter as long as we both understand what we mean.
Functional strength is not a static measure - it's very much dynamic. The term "strength" is probably somewhat erroneous and is what people who are into the game use and forget it's roots, I'm guilty of this despite being well read and relatively knoweldgeable, one gets lazy and uses terms not quite accurately enough.
The history of the expression comes from functional training and condition training. i.e. strength/power atheletes to aesthetic atheletes. There's no denying that aesthetic training involves some strenght involvement and some would argue that hypertrophy and muscle volumising is akin to strength - not so, not at all. Look at someone like Pyrros Dimas the world record clean and jerk holder for his weight class - overall a very slight person (though his legs are phenomenal) however with tremendous power and strength, his functional strength is that of his phenomenal clean and jerk ability. A gymnast, his functional srength is that to enable him to hold his weight and balance in some fantastic feats on the olympic rings for example.
However put this two in a daily life, they are no different to any other commuter on the train etc... Put them on a rugby pitch for example, and they're ****ed. Their functional strength doesn't lend them to being useful in that environment. Just like me doing the gymnast's routine, or 2.5x BW C&J. However, my range of functional strength is potentially larger and more well rounded (though gymnasts are phenomenal and in my opinion have nearly the perfect all round dynamic range of functional strength, bar perhaps lower body range).
When people/experts/begginers/etc... talk about functional strength it typically is to do with their specific area. i.e. it's functional to them. The term functional strength in itself means nothing. However if you encapsulate it with an entire physique and state that he has a good overall functional strength - it's very clear what is meant by this.
Functional strength != pure out and out strength. It's a separate measure of it's own.
I understand what your confusion is in terms of, "to be able to move from a to b, you need to have some functional strength", well of course you could define that as functional, but let's face it, we're not creatures in a vegetative state - we're all able to walk from a to b? Does that mean we have functional strength? Yes, but as I said, it's a dynamic measure. I'd hazard a guess I have more functional strength than 50% of commuters. Does that mean I can do the task of walking better? No of course not. However, overall, my measure and dynamic range of functional strength is phenominally larger than 50% of commuters. That's the key element, the dynamic range. Functional strength in itself means nothing - so I admit it was probably a bad explanation on my behalf.
Strength is a relative term, what is strong for one person is weak for another. Personally I think if you can't do BW exercises or push/pull bodyweight weights it's weak. However comparing like for like is just not possible, hence why there are weight classes, and different leagues for different disciplines.
For me the ultimate show of functional strenght would be someone like mariusz pudzianowski who has phenomenal power/strength/aesthetics but also fitness, flexibility and for a man of his size, agility and balance. If you were able to combine someone like him with Bruce Lee and and elite gymnast you'd have the perfect example of a full dynamic range of functional strength.
That's what people mean by functional strength - it's not your ability ot push a weight from here to there, it's a dynamic range of ability, and the able to the move that weight from here to there better/faster/more times if that's how you're being measured. In day to day life it's hard to quantify - in an office, the fact that I am by some margin the strongest person here mean I can do my job any better? No... leaving fitness and well being aside. However other than basics of each day, it does mean that I can lift more boxes when I move house, I can carry heavier things for longer, I don't run out of breath running up 4 flights of steps, I can carry out more physical work per hour than someone else (if I were to do physical work which I have done in the past). It's the ability to go about your day with more efficiency and be mroe functional. So in general it's hard to see, but if you look at it on a bigger scale it's very clear to see the difference.
I can't see the link you posted unfortunately I get a 403 error.
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