I had never really paid attention to who wrote or directed particular episodes until just recently. Every now and again I notice a special little touch of extra directing effort, be it a good segue from one scene to the next, especially good camera work, or unusually effective special effects. When I do check the end credits to see who the director was for that episode it invariably winds up Lela Swift.
Like I say, I'm not too familiar with the styles and differences between the directors, so perhaps Swift has some weak points by comparison. Perhaps she's more of a technical director than an acting director. However, whenever I notice a little extra directing effort - something that just catches my eye, like a really good camera angle, or starting a scene with a shot of some particular prop and pulling back from it effectively - something a little extra like that - it always turns out to be a Swift episode.
On the other hand, when I've noticed especially BAD technical directing and checked the end credits, it's invariably a non-Swift episode.
Just my .02