Bianchi concept? I believe the 53 one will fit you fine, probably 51 will be too small. I fit 56 in classic steel in the concept i had to go to 55 because the 57 was way too big.
If you use 53 in the road go with the same size or similar to that one in the track frame. The geometry is diferent, well sometimes is not but certainly the BB hight is the most noticeable thing in track frames. While a road bike BB is about 26 cms high, the track bike BB can go to 27 - 29 cms.
As u can see the BB will be like 2 cms higher, that means that the TT will be higher also, and thas the reason u have heard about getting a frame 1 or 2 cms smaller for track, since some people use the measure from the ground to the Top Tube to find their bikes sizes u end up with a frame like 2 cms smaller, again.. remember the BB in a track bike higher and the TT also.
For example, (im making up the numbers OK?) from the gound to the top of the Top Tube u have 90 cms in your road bike and u are using a frame in 54 (again, im making up the thing ok?)... the same 90 cms measured in a track bike are probably comming from a 52 cms frame, that it is clearly a frame too small or too short (depending of how u want to see it.)