The only good reason for most shooters to be weighing bullets is to cull the "once in a rare while" bullet that is really far off from all the others. They do exist, but there will probably not be very many of them in a Lot# of high quality bullets.
In contrast, measuring bullet length as a means of sorting bullets into many different little piles is something done routinely by many shooters. It is something that can typically done with a very high degree of accuracy and precision with nothing more than a quality caliper/insert. There are [at least] a couple of important considerations:
1) What bullet/segment length do you intend to sort by? BTO? OAL? Bearing Surface?
2) Will length sorting bullets provide a detectable benefit for the type of shooting intended?
The second of these considerations can be easily tested by shooting a reasonable number of groups with bullets that have been length-sorted, and those that were not length-sorted. You will either observe a difference in average group spread (or some other readout) between the two, or you will not. If there is a clear and obvious benefit, the answer is obvious.
However, as is possible with almost any sorting procedure, if you
cannot readily detect a measurable difference, that does not necessarily mean that sorting has no benefit. It DOES suggest that the benefit may be very subtle or small and not easy to detect, except possibly over a long period of time. At that point, you have to decide whether the time investment is worth it, and if so, accept on faith that over the long haul, there will be some small benefit to sorting.
Here's the humor: when you have sorted a Lot# of 1000 bullets into 1000 different sorting groups of one bullet each, you are finished. There is no sorting parameter left that will allow you to subdivide individual bullets into further
functional subgroups.