Hi Charlie K,
I asked a 'supervisor' who works Oshkosh a similar question last Wed at our local EAA meeting.  He said 'they' don't like it [when Lancairs fly the warbird approach] but they don't do anything about it.  He also added that the 'Lancairs' cause them the most trouble of all the types that visit Oshkosh... [no specific details were forthcoming]

I also asked when they expected the 135K level to descend to the 90K level.  He said to stay high until the tower frequency suggests lower.  He said that the tower controller would be looking for a clear spot below to provide a safe descent.  He reminded everyone to keep the pattern in 'tight'.  Do not string out over the lake on the 27 approach 'cause they can't see you.

Be safe!  Earl