It is a useful diagnostic to determine whether a signal may be operating above so - called random values of chance but not sufficiently robust to provide attribution of cause. (johnquiggin.com)
Provided we know the size and shape of the error in that original reading (Normal, log Normal etc) we can generate a spread of random values around our actual reading reflecting what it might be, and then for each of those read off the age that implies, using a table that randomly selects from the (smeared out) calibration curve at that value. (climateaudit.org)
I understand your general point about generating random values, except for why there need by any question about how you choose your Monte Carlo values in this case. (climateaudit.org)