If you are really good at racking, its not an issue. I think the main thing to consider is the vigor of the fermentation. If you are using a glass carboy, sometimes the krausen will literally seal up the neck. When you go to rack, you will have to break through and will have a tough time getting a clear siphon, you can always use a hop bag over the siphon. It will be impossible to dry hop though so a secondary may be necessary.
I secondary 90% of my batches because of the build up, I tend to ferment 1.1 at a low temp, sometimes it doesn't reach, sometimes it does. Either way, I usually end up bottling .9 gallons and am happy with the results. Never an oxidation issue either, but I have yet to age anything close to a year. I got a barleywine right not that I will so I will find out.
I literally rack almost all the beer out of the primary, maybe a couple ounces left, I cold crash so the trub is hard and by the end, the siphon is literally in the trub. I get a few ounces of very cloudy beer but I cold crash again a week later in the secondary. I will have only a small ring at the bottom so you can again rack pretty much all of it. Its very clear after a few days in the fridge. Hope this helps