There has been some debate within the company I work for regarding the relationship between the size of the platen and mold base. I am told the mold should cover at least 2/3 of the platen area to avoid the platen "flexing".

This does not make sense to me. Given your tie bars and location of toggles I would think you could go much smaller than that (also taking into account adjusting the clamp force).

Can someone provide some insight into this? Would be very much appreciated.