Seems to me we are talking semantics. Does playing travel on the small diamond guarantee that you make the HS team? No. Without the innate ability Daque is talking about, you won't make it. Does being a stud on the small diamond guarantee you make the HS team? No. By the time the kids are 14 or 15, others may have caught up to the "early bloomers" and the stud is now average or below average. Can a kid growing up playing rec ball make the HS team? Absolutely. With enough innate ability, kids will make it.
I don't think anyone here would argue with any of that. However, I think what many are saying is that for those with the innate ability, playing on the small diamond at a competitive level will certainly help them in the long run. Big or Small diamond, you still field grounders the same way. You still catch a fly ball the same way. You still do cutoffs the same way, bunt the same way, turn double plays the same way. You just do it on a bigger field as you grow older. The fundamentals you learn by playing at a more competitive level will allow the players with innate ability and adequate strength to be more prepared for the HS teams when they get there.
In other words, if you have two kids with the same innate ability trying out for the HS team as freshmen, the kid who played travel at a very competitive level even on the small diamond will be more prepared to play JV or Varsity his freshman year than the one who only played rec ball prior to HS. The rec player may be ready his Soph or Jr year, but the other player will be ready earlier.
I would never try to figure out what is in Daque's head, but what I gather from his posts is that without the innate ability, what a kid does on the small diamond doesn't really matter for what ever reasons. However, I would say that for those with the innate ability, even work on the small diamond on a well coached team playing high level competition will get that player ready earlier for the HS team.