So I have leased a mare, Gone to Gold and was looking at 2 stallions to breed her to : Alley Cat, who has the same sire as she does grandsire; or Stressed which puts Secretriat, Man O’ War and Alydar into the foal’s pedigree. So do I go with line breeding? What are the risks of line breeding? Or do I go with a racing powerhouse pedigree?
Here’s the hypomating link:
http://www.finalfurlong.org/hypomating.php
There are many schools of thought on this topic as you will find out.
The breeding to Alley Cat will put you in the “Line breeding” category that is about as close as you want to get. There are inherent problems you get with doing this. Along with all the good stuff you get from having Alydar that close like speed etc. you could also get conformation faults and shorter racing careers. Sort of like a comet bursting across the sky! A brilliant flash of light for a time and then nothing or they can race as long or as hard as most other horses!
Breeding to Stressed would not give some of those problems as it would be an “outcross breeding”, though there is that possibility of the problems above. When you actually breed in the real world you have the conformation of each horse to look at and be able to see if they both look the same or different. How they might look if you took part of this horse and part of that horse. One of the most common things to do is to take a smaller mare and breed her to a larger stallion to get a foal that is larger than the mare it came from.
Personally, with the options you’ve given I would you breed the mare to Stressed first and then that foal (filly) to Alley Cat five years down the road. You then get the best of both worlds.
OR … you could breed her to either Hope to Succeed or Highland Magic (Spock’s Daddy)… lol 
Had to put that plug in there!!!
Here’s my $.02…
Linebreeding can be good and bad. I think it’s smart to employ a bit of both, but just like in real life, FF horses produced from either may not live up to the expectations. Also, pedigree in FF is still a ‘young’ science since we don’t have as many generations as RL. We’ve established some ‘nicks’ (IE Worth/Rogue), but I think that the notion in RL of “the family being more valuable than the individual” doesn’t necessarily apply, especially with the introduction of created pedigrees. I’ve started to see some of it with a few fillies I’ve bred that have been much more successful broodmares, but overall, I’m not sure I could say it for certain.
I’d suggest looking for stallions based on what you want to produce, not necessarily upon bloodlines… at least initially. Alley Cat was a kick-butt Turf horse, but didn’t mature until his 4 y/o year. Stressed matured pretty normally, and had two years in top form, not to mention winning classic races. Both are young stallions, so we can’t say what they’ll throw… I’m not leaning either way, but they specialized at different things. Easy Goer is poised to be a really good BM sire, given that some other stallions from his sire line have been pretty darn successful, so you’ve got a good mare; I’d definitely look for a stallion you like with attributes that you want in the foal.
Also, as an added note on linebreeding… I know there are a couple horses that were ‘experiments’… Shanthi would be able to speak more to this I think… I owned “A.P. Diamond” who was 2X2 inbred to Seattle Slew… IMO that’s a lil’ toooo close; I don’t know if this is a correlation, but… She was successful on the track, but had a very short life. In contrast, I do still linebreed… A few examples include Sardonyx, who’s linebred to Rogue by BM sires, and Love Affair, who’s probably more a RL suggested cross (Alan Porter has been preaching breeding stallions to mares with the same sire line for YEARS… and apparently, I’ve subconsciously absorbed some of it… goooood or baaad)… I have been thinking of crossing Foxfire with The Fighting Fifty… 
And, I think there was a critter who is 2X2 Highland Rogue who was highly successful… High On Love is a millionaire and a stallion now…
I hope this helps!
-K
I believe all of those experiment breedings happened before the inbreeding code was in place. So the true test will be the offspring of those horses, or future inbred horses racing.
Ahh… gotcha Shanthi…
Lilly, here are some old threads I found regarding the inbreeding code that Shanthi mentions. They should help…
Inbreeding Q
2X3, 4X4
-K
Thanks this really helped!! I’m gonna go with Stressed 
Speaking of inbreeding: I was looking at claimers today and saw one named Seafarer whos lines are Seabiscuit x Bringdowntheocean (by Seabiscuit). I was thinking of trying to claim him (he’s 2 for 2 and just turned 3) but are his inbred bloodlines just asking for disaster??
For the $25,000 that he costs, he would be a good experiment. If you get him and he makes $100,000 career it’s not to bad a return on investment!