Hey Rugby dude, before you get to proud of yourself - you've got a semi in those shots.
As far as showers and growers - yes, a guy whose dick is 3" soft if very likely to grow another three inches, and have a 6" boner.
Likewise, as in your example, the guy with the 5"er might very well grow another 1.5" and measure up at 6.5" stiff.
The first guy increased 50%. (100 coparitively)
The second guy increased 23% (30% comparitively)
Looks like a big difference when they are soft, but not a real big difference when they are ready to use them. This is the basic idea of shower vs grower.
You said that yours was about 7" soft and about 9" hard. That's about a 22% increase. (28.6% comparitively)
Notice especially with the smaller guy, how big the percent of growth is comparitive to his size soft.
Now, based on anecdotes like these, some people construct a theory, that the smaller you are soft, the more you grow, the bigger you are soft, the less you grow. This seems to hold true with the cases above. In fact, it is true, that if you are small soft, you are very likely to grow more proportionately. The little guys with the 2 and three inch cocktail franks usually do make it up to a pretty decent 5 or 6" erect. At the other end of the spectrum, there aren't too many guys who are 7" soft and double that size when they get hard.
On the other hand, this isn't always the case. Especially in the upper middle range. The shower vs. grower dichotomy is a tendency, not a rule.
Consider that there are a good number of guys who measure in at 4" soft and shoot up to somewhere around 7.5 or 8" hard. I'm in this group.
The other thing is that the big guys are still usually bigger. To consider our first three examples - the guy who is 7" soft, is still bigger soft than the other two guys hard.
The guy with the 5" -> 6.5" hard ends up 8.3 and a third % bigger than the 3" ->6" hard guy.
The guy with the 9"er though, is 33 and a third % bigger than the 6" grower guy, and about 28% bigger than the 6.5" guy who is a shower - proportiaonatly (Copartively, the 9" guy is 50% bigger, than the 6" guy, and about 42% bigger than the 6.5" guy) So it's not the case that "erection is the great equilizer" or something like that. We can see that on LPSG It's just to say that if a guy looks small soft - he is still likely average hard.
Also, rugby dude,I don't think you don't need to be feeling sorry for anybody. They do alright. They might just be hiding their wee wees behind a towel (as opposed to letting them hang out the side of their jockstraps) because they are not gay.
Have fun.