Being a prop more than any other position except maybe hooker is about attitude.

All the same, I can't see how anyone can deny size and height is an advantage.

There are a number of subtle advantages but the best description I heard was from an Aussie.

He called it meat hanging, nice!

What he meant was that a player like Fifita who has a big frame can carry more muscle and fat but at the same BMI as a similar shorter player. So whereas Fifita can comfortably carry 18 and a half stone at 6'4'', Teanby, for example, at 5'10'' (6 inches shorter) will be happy at about 17 stone max.

In the collision that is a huge power advantage to Fifita, times that by 20 hit-ups and at least 20 tackles in a game it's not hard to see who's going to suffer more attrition.

As we've seen with Dave, when his attitudes wrong his size advantage is almost useless but when it's right he's virtually unstoppable. With the best will in the world, I can't see Teanby or most other smaller props matching that, There are exceptions, there are always exceptions but it would be a big gamble, in this case, that Teanby is the exception. Attitude can only take you so far.

Vastman thanks for putting me right he always looked smaller than other props on the park so thought he was under 6ft thanks

I'm not sure why you are both pushing the point so hard.
I don't think anyone doubts that a good big one will always beat a good little one, but there are so many examples of big ones that coaches have trusted only to find that size is all they had.
I'd rather judge props on delivery first rather than size.

Smaller props just play a different role. If you are 5'10 you don't run at the line like Fifita and your work rate needs to be higher but there are plenty of examples of players who do that.
You can't go with all small props. You won't get out of your 10 metre area. But you can't go with all big either.

So I'd prefer to judge them on what they do and how it compliments the team rather than just judging on size.

Well, I'm not if it's me you mean, it's called a debate, this is a forum isn't it? What confuses you about that?

We don't use our props to get out of our 10 m area, it always seems to be the job of the 3/4's