Size and make up of props is an interesting one.
Size versus mobility......Fitness / Technique.
It is a continuum.
It is easy too get bogged down in one end of the size continuum versus the fitness and technical side of the Game.
People will cite this team having Big Props versus that team having mobile long minute Props.
Others will cite teams with super fit high output props.
The truth is it comes down to the quality of the individuals and having the mental part right ahead of any considerations toward Size or long minutes.
The Melbourne Storm are the most successful Dynastic club of the modern era.
They are not renowned for big forward packs, rather they are associated with technical brilliance and fitness.
As others have stated the Rabbitohs and Roosters have challenged that model....even the Dogs have.....with monster packs.
If you look at those teams and consider the most important forwards in them who include these interchangeable backrow prop types:
Souths:
Sam and George Burgess ( the big and the long minutes of the continuum )
Manly : Watmough / Stewart
Melbourne : Bromwich / Harris
Roosters: ( their winning 2013 side ) JWH , Moa , Sbw
Dogs: James Graham, and a cast of big forwards.
In all those teams the key forward is the smaller forward, however it is not as simple as isolating them as a sign of the ' new direction' of the game....because all of those lead forwards ( Sam Burgi / Stewart/Watmough/Harris / Proctor / Moa / SBW / Graham ) are counter balanced by big men like ( George Bergi, JHW, Kassiano, Rose in Manly's winning year ).
The club that stands out is the Storm. Bromwich is rare in terms of his out and out size ( Lazurus was a big prop for them but he also invented big minutes for fat men under the ten meter rule ).
So all the years I've watched this game all I see now is trends, no absolutes.
Trends come in and out of vogue.
The absolutes of rugby league are mental toughness , footballing intelligence, and raw talent last.
Fitness....is a state of being that becomes possible with mental fitness . strength / resolve.
The most successful pack the Warriors have ever fielded was also their biggest pack. Little wonder Warriors fans obsess over the size dimension.
Remember too...that the most successful Warriors pack ever had a small forward will the biggest ticker (Kevin Campion) driving it.
Not to mention that 2002 side came unstuck against the fittest most mobile pack in the comp in 2002.
Balance.
Tough smaller guys who are alpha males are the pitbulls of the League world, they are worth gold backed up by some big Mastiff types.
The thing that is easily overlooked when talking about go forward is the Hooking role.
If you have a smart hooker....a director of your pack....you will get more out of any given pack on any given day from a top rank hooker.....ergo Smith has afforded Bellamy employing people like Lowrie.
Daniel Anderson managed to assemble the likes of Campion, Feka, Seuseu, Villisante, Tooki, and drive them all with the brains of Marsh.
Ivan Cleary did the opposite...by copying Bellamy's mould of tackling forward plays long minutes...people Like Luck and Mannering and Taylor became the new Kevin Campions.....people like Rapira / Lillyman and Friend, became the defensive clean up guys of Ivans style.
Ivans dummy half options only peaked for ten minutes of either half when Lance Hohaia added dynamism to a bog standard regular hooker.
So what do we need today ?
A couple of Big explosive forwards, Hoffman fixes the long minutes with Mannering and Lillyman...most of all they need a Marsh instead of a Friend.
If you paid special attention to the Sterlo clip of Shaun Johnson....you would have heard him directing the lines the forwards run....that is a hookers job ( not looking for Friend fans to quote and find argument...just making a point which is evidenced based and not anti friend or anecdotal).