Ok maybe not 5, but he has bought 4 good players per window on multiple occasions.
In fact, looking at our transfer history a funny thing struck me when looking at the summer of 04/05. It was pretty much identical to what we need in 14/15!
Then we bought RvP - a (wide)forward, Eboue - a promising Ivorian RB, Flamini - a promising French CM and Almunia - a (backup) GK.
Its very likely we buy Sanchez, Aurier and Schneiderlin + some random backup GK this summer. Ok, Alexis and Schneiderlin would be much more accomplished than RvP + Flamini were at the time, but a funny coincidence either way.