WELCOME!
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For me, Simple Simons are en extension of Bight and Lock joinings(Square, Sheet, Surgeons etc. family classes):
Favor lock being same size or smaller
lock is major loaded deformity >> defining strength as weakest link.
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Duplicating lock with Bight side(Green/Left in drawing) would give 2nd major loaded deformity, but perhaps be more secure.
If chasing security i'd make lock Double Linear Round Turn around Bight side and / or cross Tail under
>>without giving 2nd deformity / chance of weaker weak link
If Bight side is larger line (as should be when mixed) making same deformity around a smaller host
>>would suspect tighter arc to bend Ratio/more deforming geometry >> for more suspect weakness
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Note also if 1 side is lock, and is larger diameter
>>has less tension per diameter across and sometimes can't crimp into tighter/per diameter (but same overall tension) of smaller Bight side line.
>>This i think is especially viewable in Square/Reef where each side must match or 1 smaller diameter can 'crimp' into larger to Nip;
but needs both sides to do so properly and larger diameter can't crimp to Nip smaller diameter against host mount.
>>taken to Sheet, Surgeon, Simons only1 side is lock side, and it can be smaller
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i fall back into these that i was using before Simple Simons:
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i look for Round Turns coiled or stretched around the Standing Part to pull more inline than across this highest loaded area
>>All these show that form
>>Simons do give the S Part of lock a larger mount, that would give softer deformity / arc and thus be superior
>> in the 2nd pics tho it seems i get a straighter line that then may trump(sorry to use the T word)
>>i find the 2nd pic's easier to manufacture as i mount Yellow/R.hand around flat Green/L.hand, then fold Green to Bight and finish Yellow
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In 2nd pic Sheet Bend tail finish as hitch under Spart would give more 'lock'
>>But, Square/Surgeon type tail finish Draws up nicer more immediately.