Something that came about by accident, but worked really well for us in the midlands: because we didn't have great numbers (at Northampton we did, and ran two teams at each age group but others struggled) the age groups went up in twos: i.e. U12, U14, U16, U18. That meant the 14 year old who had been the biggest lad in the U14s, then found himself being one of the smaller players as a 15 year old in the U16s. This really forced a lot of our players to learn skills they had been able to get by without. The downside was that it was so hard for that smaller 14 year old, who was now tiny as a 15 year old relative to the U16s.

I do remember my son's side at under16's were always getting accused of playing over age players in the Hull junior league despite the fact of a very well policed registration photo ID card system in place. We just had some very big well advanced lads at the time. Having said that they were average & mid table. What Greg Inglis has got as well as his unique build is a superb rugby brain & most important a determined will to be good at his job.

Nrl is reviewing interchange numbers. Most are calling for a reduction to 6. The days of 125kg forwards playing 20mins are numbered!

Still plenty off small guys in nrl. Slater, tomkins, Luke, Barba etc etc. wingers and centres may be heartier but if your good enough you'll be big enough

If NRL goes to 6 interchanges how long until SL and INternational rules follow?

Not only will the interchange rule reduce the number of giants who can't do the minutes, the likely hood is that we'll see the hardworking big guys start to leave a few more gaps for the little guys towards the end of the match.

There are some colossal differences in physical size in age group rugby, mind you there are still some hue differences when you look across the pro game.
There does com a point when the "big" kid can no longer just run through the opposition and the argument is that the later developers should be equipped with a different skill set and
certainly the smaller players need far better tackling technique (which helps them later on)

Having said that, when you look at many of the guys that make it, they are above average size/weight and the game at the top level doesn't suit smaller people, with some obvious exceptions.

Other sports are similar, with the early developers having a massive advantage.