It has been discussed often, the need to laminate both sides of MDF/Ply tops. If I have laminated two sheets of 18mm MDF for a top, will it still need laminating both sides?
I did exactly what you are doing for my table top two thicknesses of 18mm mdf laminated on one side, left a week and it warped. Though i would guess that you could get away with it if the top was well supported and you got it attached quickly, any doubts do both sides just so much less grief