In the 25 Oshkosh conventions that I have attended, I've flown into about 1/3 of them, and nearly every arrival has been "interesting."
I've been behind the low-n-slow kinds and instructed by ATC to go around them. I've been cut off and had to react quickly to avoid unfortunate issues. I've been upside-down. I've been passed. Even this year, both my arrival and my departure were not without issue.
I arrived over Ripon at exactly 1800' and 90 knots, trimmed and quite comfy. As I made the turn over the water tower to follow the tracks, I saw a shadow above me. A Bonanza was zooming overhead and to my right. I assumed that he was on the higher arrival and would drop in far ahead of me, but noooooo ... he chopped power, dropped his gear and slid in right in front of me! I'm not sure he even knew I was there. The only bright spot was that he made an admirable circle-to-land approach that was in tight, not the typical airliner/Bonanza approach.
Thursday morning, I was killing time for my tent to dry. With only an hour's flight to get home, I was in no hurry. The early departures were lining up quickly, and I didn't need to clog up the system.
Then the Breezy crashed on 36R. That closed the airport for over an hour, and that meant that the taxiways were lined with anxious pilots.
When they opened the airport again and the taxiing aircraft began to move, I packed up my gear and bid friends adieu. I joined the conga line for 36L and taxied for an hour before it was my turn to blast off. The controllers needed to work in the planes that had been holding while the airport was closed.
[Side note: The FAA controllers I worked with this year did not seem to be up to the standard that I'm used to. Aircraft ID was poor and safe aircraft flow was marginal, IMO.]
After 3 Sonexes departed in front of me, I was at the hold line waiting for instructions. The radio was silent. Apparently, the radio of the controller at the hold line had chosen that moment to go belly-up. I could read her lips saying to the other controller, "I can't hear you!" I looked to my right and saw a C-17 on a two-mile final.
I looked pleadingly at the controller on the hold line, making gestures that I can get out before he arrives, but she just looks at me and shrugs. So, I sat there and watched the behemoth make a low pass. I hear some wag say over the radio, "Don, that C-17's gonna squish you like a bug!"
The monster passed overhead and the controller said, "Gray RV with the pirate tail, cleared to take off 36L, left side!" I shoved in the power and mentally tried to imagine what paths the huge cargo plane's wingtip vortices will take and how I can avoid them as I turned to line up with the runway. I decided that fast and straight up is probably the best course of action.
I quickly climbed above the C-17's path and, as he turned downwind, passed over him and out of potential harm's way. As I was climbing out, I heard the somewhat panicked controller say, "Don't let anyone else take off until the wake turbulence is gone. We nearly lost that one!" Sheesh.
The moral of the story is: Be prepared for the unexpected. This ain't your mama's airport. If everybody plays by the rules (the NOTAM), there are few issues. However, there are those who won't, or don't, and you have to be prepared to adapt, improvise and overcome.