Personally I prefer to animate chunks of pixels instead of lines. Lines are really high maintenance in pixel art so I consider them part of the end process.
I actually wasn't referring to doing low-pixel line work. The resolution that the original author is working at would allow them to do decently high-resolution sketches initially, and then scale it down for the final pixel rendering. I was also specifically suggesting stick-man drawings to flesh out the initial skeleton of the character, not the line-based pixel outlines. A stick-man skeleton for a characters animation will give you an idea of how you want it to move in the animation before you start drawing the structure over it.
Essentially, given the digital tools at your disposal, there's no reason not to use a workflow closer to how a traditional animator might go about it, and then simply scaling your work down to the necessary pixel resolution once the animation is already at a point you are happy with. Actually working at low-resolution is only useful if your game is going to be EXTREMELY low-res and pixel-based by its very nature. We're talking 16x16 or 32x32 pixel hard limits for individual sprites. If you're working at anything above that, you might as well refine your workflow to allow for a more natural drawing and animating experience.