In photoshop CS6, if you create, for example, three text layers and all of them have, let`s say 12px and then you pick one of them and increase the size of it with transform tool (I reapeat, not by adjusting value in the Character box, but by ctrl+T, transform tool) the new size of this layer will be, for instance, 15.22 px.
Now, if you select all three layers and you want to readjust their size from the Character box by 14px, they don`t resize properly, I mean not all three fonts will have 14px in the end.