I found the blog piece by Professor Tao that I commented above seems to be relevant to this question:
http://terrytao.wordpress.com/advice-on-writing-papers/dont-overoptimise/
I hope the OP will tell me whether this is, in fact, relevant to the issues he wishes to consider.
If this is on the right track, perhaps "suboptimal", "not sharp" or "unnecessarily weak" give a better description of the phenomenon than "wrong"?

