If I was laid off by a company I wouldn't go back unless I had no other choice. If a company didn't see your value previously and now it supposedly does, what is to say it will not change again in the future and fire you again? A lot of companies do a last-in first-out approach and are cyclical about hiring and firing to please shareholders. That's where these tech companies are at now.
Also who wants the potential of a CV where you were laid off twice by the same company? It'd be like them taking your CV and wiping their arse with it before handing to back to you as security escorts you out of the building.