Throttle plate gunk

[Ricardo]

I pulled the manifolds to replace a suspect manifold gasket and while cleaning things up, I discovered that the throttle plate and outer intake bore were pretty crudy looking. Since this is the side that the crankcase vent tube comes in, I'm guessing it would be normal to see a build up of oil residue?
The stuff came off easily enough (lacquer thinner), but the build up was significant and it has me wondering.
My compression is good and I don't use much engine oil (Mobil 1 5w-50) and my car has the intake heater. Mostly highway driven.
Is this a part of regular maintenance work, that we should be aware of or does it make any difference?
Ricardo
'67 250 SL
PS...I finally changed out the SE motor mount arm and the engine sits a good 3 cm. (1 1/4") lower...now to fix the dent in my hood  

[Cees Klumper]

I have looked at a fair number of these throttle plates and intake bores and never noticed any real build-up, only slight dark color on the surface - no crud. On my engine, before the rebuild, I did have oil deposits in the air filter canister, which since the rebuild does not occur anymore.

Cees ("Case") Klumper in Amsterdam
'69 white 280 SL automatic