[r-t] Extension question

Mark Davies mark at snowtiger.net
Tue Jun 28 22:44:46 UTC 2016

Ted writes,

> I am not familiar with all the rules of extension but know only that I
> have often thought they seem very illogical.

The rules codified in "Decision G", which I suppose you are referring 
to, are not the only way of imagining how you might extend (and 
contract) methods. However they do have some logic to them, for sure. 
They express basic ideas about the structure of a method that perhaps 
ought to be preserved through extension - for example, its symmetry, the 
type of its treble path, and the pattern of place-making in the lead.

However, whenever you have some nice clear logical ideas about 
something, and then sit down to try and codify them, mostly you find the 
detail all turns out to be disappointingly more complicated than you 
expected. "Decision G" is no different. The original drafters of these 
rules had some good ideas, I think, but chose to express them very 
concisely without much in the way of explanation. The result is 
something that's very obtuse, and hard to work with by hand.

We've debated before whether there is indeed any need for a set of 
method extension rules, or whether a free-for-all should be given for 
bands ringing and naming methods which they consider to be extensions. 
My view is that, for a method to be an extension, you ought to be able 
to demonstrate a rational algorithm which can construct it from its 
parent (or vice versa), and which also produces nice extensions for a 
range of other methods. In this milieu, "Decision G" is almost certainly 
not the only such algorithm. In fact someone on this list (was it RAS or 
Ander?) came up with another promising one a few months back.

> If an extension of a place
> method is not allowed because it introduces dodges then perhaps the
> answer is to consider the extension as the base stage; the dodges will
> be maintained in further extension but lost, due to lack of dodging
> positions, in the contraction. Does that then become acceptable?

Well it's not acceptable under the current "rules" but I have a lot of 
sympathy for that viewpoint. A base stage having zero of something, with 
the next stages 1, 2, 3 etc of it, seems perfectly reasonable. We have a 
good example already in Bristol Surprise - the Major method has no wrong 
dodges, the Royal one, Maximus two, etc.

Perhaps this tells us that the Place and Bob classifications aren't 
actually terribly useful. I'm not sure anyone would be too sorry to see 
them quietly fade away, would they? (But maybe this is only because 
plain methods aren't sexy any more - I can imagine an uproar if TB, 
Delight and Surprise were similarly merged, and there would be serious 
naming conflicts there too).

> Stedman singles has no dodges but they appear nicely at doubles and
 > above; does this mean Stedman Doubles is not a legitimate extension
 > of Stedman Singles?

Robin Woolley has sent me this response:

"The singles is unrelated decisionwise to all higher stages. Suppose the 
p.n. of the Singles (whole 12s) to be At all 
higher stages, 3rds place becomes the back place so this would be on five bells, etc.

"[These methods are] very false in the plain course and given that it 
seems the word 'method' [was] used to mean 'way of generating the 
extent', it seems unlikely Fabian would have bothered about it."

One thing he is pointing out here is that the current extension rules 
view lead/lie places as different to internal places, so the 3 place 
notation in Stedman Singles must be treated as a lie in all extensions. 
But on the other hand if you start from Stedman Doubles as the base 
method (which as he says is true, so also classified differently under 
current regulations) then the 3 pn is an internal place - it must stay 
internal, but doesn't have to (say) move up to 5 at Triples.

Again, you can see a bit of logic in this idea that lead/lie is special. 
But you can always think of special cases that test what initially 
appears to be "globally-sensible" logic.


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