I would have to search one of my older books for the 1% figure. It has been years since I read that statement.
Keep in mind I am not discounting all scientific findings, so don’t throw me into that wagon. Science has and will make great discoveries in disease control/prevention and many other areas.
But for someone to say that we can say how old a rock or fossil truly is by scientific means is just not true. There are too many ‘scientific assumptions’ thrown into that mix.
Uncertainty is accounted for in the +/- tolerance of the dates given. It is accepted scientific practice to be extremely conservative and give the widest margin of error when citing an age.
The thing you have to accept is that time is relatively linear and time related coefficients are fairly constant. The the result is that quantification of time is mathematically derived and mathematically repeatable and reproducible.