General Report on Tunny
25C Page 159
be ignored; for example very strong evidence would be required to justify running B's for any ΔΧ. This remark about B's assumes that B's really are B's and would be invalid if it were not known which way round the wheels were (25D(f)); or if (e.g.) ΔΧ2 were very uncertain, B's (against D's) for ΔΧ5 would not be unreasonable, because many apparent B's would in fact be 5's.
It is accordingly necessary to use judgement in choosing and decibanning runs, ignoring improbable runs, 'knocking off something' from the crude decibanage of runs already used in making the wheel, and generally exercising discretion.
'Knocking off' is needed till the wheels are almost complete and correct, when the effect becomes negligible.
Note: in decibanning U's for Χ2 for example 
is simply 
25C GENERAL PLAN OF WHEEL-BREAKING
(a) Typical description.
A complete wheel is comparatively rarely obtained from a single wheel-breaking run. The sort of thing to expect is more like the following. A rectangle provides incomplete ΔΧ1, ΔΧ2 wheels. Runs for ΔΧ3, ΔΧ4, ΔΧ5 are made, in an order depending on the particular fish link, until a significant one is found, say 5 = /1 = 2: this gives an incomplete ΔΧ5, using which 4 = /1 = 2 = 5 is significant for ΔΧ4. A 16 letter count indicates the most suitable runs for improving ΔΧ1, ΔΧ2, ΔΧ3, ΔΧ4 all of which are used, a fresh letter count being made whenever a wheel changes considerably. It is now possible to obtain a significant run for ΔΧ3. A 32 letter count indicates suitable runs for strengthening ΔΧ3, and another count indicates runs for improving ΔΧ1, ΔΧ2, ΔΧ5, ΔΧ4, ΔΧ3 in turn (unless there are contradictions, it is preferable to treat wheels cyclically), and finally, perhaps after going round all wheels several times, and with the aid of methods yet to be described, all wheels are made certain.
(b) Wheel sheets.
The whole process is unmanageable unless the results at each stage are recorded systematically. This is done on five appropriately headed wheel-sheets, each containing the runs for one chi wheel.
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