Pull-off question that has been bothering me

I have been playing guitar for a little over two years and think I'm reasonably good, but I have a question about pull-offs that has been bothering me for a long time. I have a hard time explaining it, so bear with me. I hope that if I'm doing this wrong, I can unlearn a bad habit (which is hard to do two years into the game). Thanks in advance.

Anyway, here's my dilemma. I'm talking about multiple pull-offs (we'll use a chromatic scale for this example). Which of the following are you supposed to do?

1. Place all four fingers on their respective frets, then pull of one at a time until only your index finger is remaining to let the note ring out.

Or

2. Place only two fingers on at a time. Ex. Place pinky and ring finger on fretboard. Pull off to ring finger. Place middle finger on fretboard, and pull of to middle finger. Etc.

So I guess what I'm asking is do you quickly position all fingers on their frets before pulling off, or do you position your next fingers on lower frets at the same time you are pulling off your current fingers? I know that may have been confusing, so if you have any questions as to what I mean, let me know.

I've always done it the first way, but honestly i think it's a matter of preference. I dont believe either way is the wrong way.

I'd prefer the first way 'cuz it's better to develop all of your fingers. Thats what I think. I maybe play for almost two years, but I always try to do pulls & hammers with all of my fingers. Now I have a problem with hammering with my pinky, when my middle finger is already fretted. Like holding a barre chord and fretting some note withe middle finger and I have to do a few notes with my ring and pinky, which often tend to be hammers with the pinky and thats pretty hard for me to do it clean and hit it strong enough, although I play an acoustic.

I usually place all my finger on the fretboard. I do it mostly to get a better control over the pull-off from the pinky.

I would believe that someone with great finger independence and good strength with his pinky and ring finger could roll-it instead of placing all fingers on the fretboard.

The only advantage I see from rolling it is that it would be faster since you wouldn't have to wait for you previous run to end before starting the multi-finger pull-off.

Honestly, I rarely pull-off four finger runs. I either end up with 3 or if 4 notes are required, I would pull-off the first ones and slide to the last :)

If what I'm playing fits with it, I'd go with option 1) - all four fingers on the string and pull one at a time.

However, there are times when I'll do it the second way - specifically when I'm playing something where I'm skipping strings and the run doesn't lend itself to having all four fingers tied up in a line. Also, like Benoit says, I'll often slide down to the last note.

I think the best approach depends totally on the context - but I don't think that either way will prove a limitation in the future....

Thanks for the replies everyone, I'll start trying to develop both ways more.