Hi Keith,

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Given the nature of uncertainty in carbon dating its a reasonable enough statement to make.

If I understood Michael’s answer correctly, there is still uncertainty for the Old Kingdom, which allows it to be shifted into the past by 1-2 centuries, but not into the future, since the radiocarbon ages for the Old Kingdom are clearly gravitating to earlier dates (by 1- 2 centuries).
The accuracy of the radiocarbon dating method for the Old Kingdom is ~ 70 years, for the Middle Kingdom ~ 50 years, and for the New Kingdom ~ 25 years (estimates from "Radiocarbon-Based Chronology for Dynastic Egypt").

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I often wonder why they don't employ dendrochronology on those beams still present in the Bent pyramid, it might help clarify things.

A master dendrochronology for Egypt has not yet been created, there are only a certain number of unrelated floating chronologies created on the basis of the study of specific samples (material of coffins, logs, etc.). In this situation, the relative position of these floating chronologies depends on how accurately the studied artifacts are dated by Egyptologists (royal lists, etc.).

Logs from the upper chamber of the Bent pyramid and wooden supports from the Medum pyramid were investigated by Kuniholm and local floating chronologies of short duration for the 4 dynastiy were created (see p.34 here).

Alex.