Graham, I know what you mean. I've provided some tales about climbing to an author who's book is nearly a decade away (coincides with an anniversary) and I questioned why so far ahead:
A who did first winter ascents with B died very suddenly last year. Fortunately I have a full account from B. C has gone senile and can’t remember anything according to his wife. D has Parkinson’s. E is drifting into senility and it’s very difficult to get anything out of him according to his son, etc etc - got to get on with it!