Salam,
As Aamir bhai mentioned, age factor is also important and with time the ingredients tend to react and can reduce its strength.
As far as Mirror Glaze16 is concerned, it is oily, in fact very oily. Saying this, one should be very careful in applying it. Apply a very thin layer of it and do panel by panel (No matter which wax i use, my preference is panel by panel). Don't let it to cake because it gets very hard to take off.
The way i do it, i use it as glaze, massage it to body and take of at the same time, this way you will also be masking the swirls. This way it get absorbs to the required limits and excess is taken off, so no hazing, no caking.
Overall, Meg16 is hell of a good wax.