"From the context I would say railed = "park and ride".
Park and ride is carving. But it is the lowest form. No steering is happening. A skilled skier can steer while carving. And no I dont mean adding pivoting. You can leave perfect pencil lines and alter that line by increasing/decreasing the edge angle and/or altering your fore/aft pressure distribution along the skis length.
Carving with the steering described above is the goal for hardpack skiing, but something most will never even realise is possible let alone attain.
Park and ride is what many do...they simply tip and ride. They are usually limited to one particular arc (ie no steering ability), which due to thier lack of skill is typically long and shallow."
and with Bushwacker, and not at with the rest of the replies.
Passive, ski design arcs are often called railed,
more active carved turns with a variety of progressive edge angles, working w/ pressure, and even steering are more often considered carved.
also, when you start finding more forces, those "pensil lines" can get bigger was well, and as opposed to a less dynamic turn, this often shows a more dynamic turn creating more impact on the surface w/o skidding.
not the skidding is bad....
as those of that ski mountains with a real pitch and obstacles know very well. blending the carve, tip/tail following the same exact path, with the drift (some horizontal displacement and skidding) in the ideal amounts to put the skis exactly where you want them, at the speed you want them there, that is art to me. railed is a nice drill, to work on balance and learning to contol the natural skid.
(haven't posted in awhile, but just got back on the skis, and skiing a flat mtn w/ a fun group, some of them key players on this board, and along with noticing some good skiing, I also tend to notice a propensity for 1 turn., here's what I wrote to one of the skiers I skied with and a good idea for those more "park and ride" oriented skiers.
To be sure, that is one of the things that bugs me about skiing N*, you end up making pretty simple carved turns over and over. No need for speed control, no need to actively shorten or lengthen the radius. I enjoy that turn (more w/ a shapelier ski), but I really like to shape the turn more, and put the ski places, that is why I do most of my free skiing at squaw, you have to direct your skis to the right spot, or things are not good. At N*, for early season, I would think about shortening up the radius on the little steeper pitches, and the opening it up in the flatter ones. Also, as you are coming up on a breakover, think about reducing the radius a bit at a time, like you are going down a funnel, slightly shorter, slightly shorter, to shorter, the open it back up out again the same way, from funnel to hourglass… that will tune you up quicker to DIRT, Duration, Intensity, Rate, Timing, of the movements.