Superior pedigrees are the master, evolutionary templates.
We shall access their ‘unforgettable’ strains and their emergent strains.
Remember ‘thoroughbred’ originally meant carefully-bred.
In this blog-creation & its writings, we look at structure defining ‘devil-in-the-details’. TBL strongly advocates the maternal, as key-to-the-trade, the sweet-spot(s) of broodmare sires, grandsires as both ‘pivotal’ maternal and paternal nucleus important.
At grandsire/great dam ‘family-range’ beyond…. running back-through to the individual – view the cyclic families in generational rotation where past becomes present & future, as if all in ‘unity’ accompanied with the penetrating strains which should define ability/capability.
Take importance why family relationships ‘bond’, strengthen to same band BUT incorrectly may ‘weaken’ (downgrade) bloodlines. IF families merge too close or to out-crossed the imbalance may occur and where TBL will say, many selected sires are just woefully & wrongly planned to equal ‘horse-wastage’ going nowhere. Its dysfunctional.
Additionally, within the workings it is helpful to digress where the rotational-generational cycle is sitting to ‘merge’ or create the best possible balance/structure. The better criteria and advantage to apply is within 5th – 7th removes.
use it or lose it…. wrap the lines, ‘strike’ upon strains by utilizing female family numbers
Also comprehend the ‘efficient’ maternal lines where they periodically ‘hold’ for 4/5 generations. Think Nature, the Sigmoid curve. 
The engine and structure has to go complete, innately so. Do not just pin-point genetic-monsters: Mr Prospector, Northern Dancer, Native Dancer, Sunday Silence, Sadler’s Wells & others etc etc, as descendant sons & daughters progress/merge……..
The broodmares projected as black-type producers e.g. Dancing Show (8-f) does not mean fast track to superior progeny: they are however better ‘qualified’ in breeding circles at producing the black-type.
Dig into FAMILIES, BLOODLINE FAMILIES/GROUPS/BANDS which affiliate or co-affiliate.
( …. seem to recall where Federico Tesio would take importance at 7th, 9th, 12th generations. There is further reference to it – Thoroughbred Breeding: A MASTER OF TIME )
What would Nature seek to apply?
The herd dynamics in wilderness, fires primordial force. What is her crucial rule upon an artificial mating/breeding terrain when unfashionable sire/mare meet, CAN produce the spectacular California Chrome’s, American Pharoah’s, Sunline’s (providing this is the breeders aim, rather than the commercial here now, gone tomorrow….)
Sunline
Back to the Wilderness – we may think surviving, instinct, durability, tough. The matriarchal feral mare who smells ‘water’ and finds, or smells danger of wolf to lead the herd away from danger. And the feral stallion who must fight and select himself for supremacy and the right to breed. The ‘unwanted’ left to isolation and fend for themselves or tag along at distant. This is ecology in action.
(on stamina & breeding)….. regarded ecologically as one of the assets of the breed, and one might even return to popularity at some future time. (1977) Franco Varola – Typology of the Racehorse
Could natural-intelligence ecology transmit to commercial environments. After all, it is a precocious foal who appears to know it has destiny.
The geno/phenotype verve, for speed & stamina is all encompassing but phenotype may not be thoroughbred-perfection, but the Verve raw vigour appearance, gait-spring, animus-intelligence, x-factor plus as dual purposeful fit. In my eye it astonishes how individuals are missed and opportunity overlooked at auction.
Again….the focus at ‘highlighting’ mature grand-siring lines cannot be at all minimized. They’re influential, unique, ‘individualistic’: a short supply availability in the greater breeding population and think Nature plainly begs for dominant-diversity back-to-the-herd.
*TBL Diversity ‘hit-list’: they are the descendants from/via Success Express (USA): Semipalatinsk (USA). 
Take note, stallion pedigrees – Savabeel (AUS) & Spirit of Boom (AUS) and of course progeny!!!! Plus, you know who *Winx – Winx’s phenomena.You might like to check out this blog: Moving on from Danehill
Bold Ruler (USA) is moving strongly. Think ‘on’ these old-master lines as diversity, a change from same duplication at in-breeding.
Again….let’s ask ourselves why would Nature keep at recycling ‘same’ XX, XY herd, and progeny without requirements of fresh diverse blood to the pool.
Great breeding is evolutionary ecological movement.
Bold Ruler – photo credit by http://www.spiletta.com
I hope your broodmare potential is deeply examined to appreciate her origins, the inherent worth is explosively utilized.
As a case study in-bred Semipalatinsk/Success Express bloodlines – the NZ Karaka May Sale features a breeding proposition Lot 370 – https://www.nzb.co.nz/sales/pedigree.cfm?sale_id=205&lot=370.
with fee variance!! Potential sires considered –
*Real Impact (JPN) – the paternal Y strain Turn-To (IRE), corresponding great, great maternal sire Semipalatinsk. Hold Your Peace (USA) 4 sx5D
*Trust in a Gust (AUS) – Turn-To (IRE) , as above. 6sx9sx8sx7Dx8Dx7D . Prince John5sx7D via Success Express.
Ribchester (IRE) – Last Tycoon 4sx4D – where I like!
Puccini (NZ) – Marscay (AUS) 4sx5D – where I like to.
The Thoroughbred Link 