Indeed, and I am sure we all do that.
However, if I were advising a newbie on a breed, where they want to lamb outdoors, I would suggest Shetland every time. Because I have found that breed to be very suited to outdoor lambing and the breed most likely to have no lambing issues and no mothering issues, no matter who you buy from. (Although I would of course always advise a smallholder, if possible, to buy from a flock where you can see that the sheep are well-handled, calm and friendly.). I have also found them to have generally good feet, to have generally a fairly high resistance to worms and to flystrike. And of course the fleeces are usually great for crafting and the skins for small, soft sheepskins.
[member=27335]vfr400boy[/member] I am so sorry we have gone off down a bit of a rathole. But hopefully you can see that the advice would be, if you decide it is Zwartbles for you, then the thing to do would be to buy from someone who can tell you how and why their sheep will be trouble-free because of all the culling out of problems they have done, and also who lambs them outdoors without penning them up when they lamb, so you can be reasonably sure their ewes will mother up successfully outside. And I would concur that you might be better getting two or three in-lamb ewes who have done it before (although there is always a question as to why the seller is selling those ones and keeping others for themselves, so use your intuition as to how honest the breeder is being with you on that one :/)