Capers...you are quite right - nothing ventured, nothing gained.
I think it is worth pursuing an appeal if you think it is right for your child. Otherwise, you would always be left wondering "what if". However, even though it might be the obvious thing to do, it still takes quite a lot of courage to do it IMO.
I love Cindy's line "the more goals you create, you are bound to score one" - I never thought of it like that before. We only have one feasible option for grammar school, but we can still work on a Plan B (and possibly even Plan C, D, ad infinitum!)
When I read stories like Turmoil's, though, it does make me wonder what type of case does get through if one like that doesn't win? I can only guess that the prejudice to the school was considered to be higher in this case, difficult to understand how.
Best of luck.