TakaSo even though it's kind of redundant, if anything, 'in relation to the target' is within the scope of the that-clause; it doesn't modify the verb 'say.' Is that how you see it?
To me it's technically ambiguous; it could be either. Compare these similarly-structured examples:
This is the hall in which I made my speech about civil liberties. -- "in which" modifies "I made my speech"
This is the principle to which one could say the judgement adheres. -- "to which" modifies "the judgement adheres"
So, the sentence structure does not distinguish. However, in your sentence it doesn't matter because it doesn't affect the meaning. The only meaningful way that "in relation to which" can modify "say" is if it's referring to the content of what you say. And that's just the same as directly modifying "concerto A got nearer to the target than concerto B".
TakaIt would be hard if not actually senseless to specify a target in relation to which one could say that concerto A was better than concerto B.
Exactly right.