Would it boost your weight loss? It may do - it may not.
Would it be healthy - all depends exactely what it is you're planning on eating and how much to ensure you have a recommended daily allowance of all the major groups.
Would it be sustainable - i (personally) doubt it.
Whilst (i'm going to assume the OP is an Extra Easy person - as that's most common these days) EE says 1/3rd of the plate should be superfree, that is a minimum guideline and the more the merrier - and success express is 2/3rds of the plate - I think it'd be hard to do without incorporating some kind of pulses (typically not superfree) or high protein (meat/fish) food stuffs.