I will compare 105 vld's to 103 vapor trail, as most of my hands on experience is with these two. I will echo most of what Jason said, but I still sort. The difference is how long sorting takes, and how many things need sorted. I've had a phenomenal barrel that shot one of the best lot of vld's I've seen in 2009. The same barrel in 2010 was able to beat the 09 aggs with Spencer's, even though starting the season with 900 rounds on the barrel. It wasn't a huge margin, although if I had to be honest, 2009 had more good condition days.
I personally don't sort bearing surface length anymore. I still use the stand however. The Bob green tool is a wonderful idea, and an important part of sorting, but I find it hard to get along with (repeatability issues). I use my granite stand, a one tenth indicator (without attachment), and a couple different comparators. I first measure base to ogive (larger comparator), and then base to higher up the ogive (smaller comparator). At this point I now have effectively qualified the ogives, in effect what the green tool does. For me, when measuring the same bullet, my method is was way more repeatable, which lowers the extreme spread of my own error.
Now, one thing I've found with the vapors so far, is that the two above measurements correlate. This means, my piles aren't splitting when I switch comparators, and this makes life much easier. EDIT - I want to make clear, I NOW only use the one comparator on vapors. After discovering the correlation to the green tool, and also the small comparator. I do check every loaded round, and any odd seated ones are used for sighters. Assuming my seater stem didn't change diameters, this effectively Bob Green tool sorted/double checked them.
Since I qualified using the bullet base as a datum, it now means something when I measure OAL. OAL is my last step, bulking them into .001 ES piles. I take the first two measurements into .0005 piles (I know, notice the baldness).
My piles of bergers of course are more of each. But I also check for varying diameter. Which sucks by the way, it's hard to measure. What I do is lock a micrometer and basically use it for a go gauge. I do not check vaportrail, the man does good.
The sizes of the piles are much larger with vapors. The bergers got the edge on the amount of piles though, lol.
From here I will work up a baseline load, seating, powder, neck tension etc. Once I have a solid load, I will now test measured bullets, vs measured and pointed, trimmed and pointed etc. Varied amounts of the above, keeping notes on length and meplat diameter(best I can measure). All testing done at 1k, so I can make out the difference, and always in a format that mixes conditions evenly throughout the test. Because conditions vary from day to day, I always take the last sessions "winner" to test against whatever else I dreamt up to test next.
That's about it, pretty easy really.
Tom