[r-t] Method extension

[Don Morrison]

On Fri, May 1, 2015 at 3:55 AM, Andrew Johnson
<andrew_johnson at uk.ibm.com> wrote:
> That's sensible. If M8 extends to Ma10, Mb10, Mc10, but Ma10 somehow is
> the 'best' extension,

Am I correct in assuming "best" extension is shorthand for "is believed,
on average, by an ensemble of practical ringers to be the best extension"?

And further, let Ma10 extend to Mu12, Mv12 and Mw12, with
M8->Ma10->Mu12 being the consistent path. And Mb10 extent to Mx12,
My12 and Mz12 (am I right in thinking this is all possible?).

If M8 had been rung, but none of the M?10s have, is it guaranteed that
Mu12 is a better extension of M8 to max than is Mx12? And, if M8 had
never been rung, is it guaranteed that Mu12 is a better extension of
Ma10 than is Mv12?



-- 
Don Morrison <dfm at ringing.org>
"If evolution happens, and frankly I've always considered it a bit
of a fairy story, it has to happen fast. Look at lemmings, for one
thing. The little blighters keep chargin' over cliffs. How many
have ever changed into birds on the way down, eh?"
               -- Terry Pratchett, _The Last Continent_