At around those precisions ...

I meant "At around those exponents... ".

I would have made this correction as an update to the original post .... but the option to make that update is seemingly currently unavailable.

UPDATE: hippo has just pointed me to the thread where this recent change (which occurred while I was away) was discussed.
++ to BrowserUk for pushing for the option to re-instate the update box to its original location and ++ to jdporter for enabling that option.

Cheers,
Rob