Safer? Debatable. For example, if the climb limit weight in the FCOM is 63.1 - how do you know if it's 63050 kg or 63149 kg? 99 kg may be one passenger with luggage you will have to offload, because you're not sure if you can satisfy the certification performance requirements.
I hardly think an FCOM limit of 63.1 would actually be 63050. They'd obviously round limiting values down, unless they were stupid.