If it's a concern, it is very easy to just remove that oil pipe and blast it out with some carb cleaner to be sure it is clean and free flowing at all of the holes. I'm not sure I would bother if your cam lobes look uniform and healthy and you are measuring about the same amount of wear down the length of the cam whenever you adjust the valves.
In the process of bringing my engine back to life after sitting 18years I did notice more cam wear at cylinders #5 and #6 and so I investigated further because it didn't have many miles on it.
I built an electric oil pump to flush the gunk out of the engine (it was bad) and also to observe how oil was distributing down the cam. I could do this with the engine off for 10's of seconds so the mess was tolerable and oil had time to drain back. I'm not sure I would recommend running the engine and spinning the cam without a valve cover unless you are ready for a mess. Sounds like just cranking is OK, but that may not be fast enough to reach full pressure, certainly not when hot.
Anyway I found out that when the oil pressure is lower (<30psi), on a hot engine, the oil streams nicely over onto the cylinder #1 cam lobe but would only drip straight down back at cylinder #6, entirely missing the cam! This seemed like a possible cause for more wear and heat back there. So, I actually repositioned my oil pipe a bit more over the cam back by #6 so that when pressure is low it will still at least drip on the spinning cam and allow some lubrication at hot idle. I suspect at higher RPM there is no issue, (another reason to go fast :-)
I also integrated my electric oil pump into permanent engine feature so I can reach full oil pressure for as long as I want before ever cranking the engine. Maybe overkill, but I feel better not listening to the extra engine noise that happens on a cold engine before the original gear pump is able to push oil up top...sometimes a good 20-30 seconds later.
