I can't run dogs running too wide. In my experience, that is a problem that escalates as they get older. It starts with a reaction to pressure early on and develops into a go to behavior when dogs do not want to face the music--an easy out. Precision required of top runs is nearly impossible with such a dog, as they will take swings at moments of grave inconvenience and hemorrhage points for sloppy turns, or worse stay out of the park when you are trying to shed; or what about a criminal cast off when shovelling them in the pen is demanded. How can a wide one inspire confidence on big unfenced fields as they run out? Which nonsensicle place will they end up? I can't abide a wide dog. Nor will I breed to it.
Too much eye can be a deal breaker. They will spoil outruns by pulling up early. They are shortchanged in the free flanking department. They hesitate when asked to walk up, pretending to be considering options. They lock up at the pen, letting you down even if they just laid down a good one around the course. They will hesitate when they should be fluid, enlisting sheep confrontation as the sheep will always peer back at them, an ovine equivalent of WTF. They provoke questions for which there are no answers. They explode in a cheap grip when tension gets the better of them. Don't run it. Don't breed it.
I don't mind training through questionable power. Sometimes dogs, who are inspired can workout techniques to handle aggression from sheep. You as a trainer can be a confidence builder. However, be prepared for failure, as it doesn't always work out.
I saw a dog last weekend who was remarkable as a youngster for being a poor outrunner--crossing, confused. Many handlers I know, me included might have given up on him, but his handler took him back to basics of short successful outruns over the training year. It worked. His handler believed in him. He has become a proper dog, with big difficult outruns under his belt. Dogs, just like people, can develop in good ways in the presence of compassion and faith. your job as a trainer is to sideline liabilities and showcase assets.