I watched a TV documentary on Joanna Mathews before she went into Miss Olympia Contest. For 7 days prior to the contest she only had water and whey drinks. She said that she had never felt weaker.
Yea i wouldnt be fooling around with something like Whey Protein Concentrate pre contest.....I would go with the highest quality Isolate you could find....and the last 2 weeks is up to your prep trainer...listen to him and do exactly what he tells you to do....some like to go in on food only.