What is the worst you are doing to the engine by reving quite high when cold?
Get a small amount of engine oil, put it in an empty drinks bottle or glass jar and stick it in the freezer overnight. Have a look at it the next day and see how thick it has become.
When your motor has been sitting outside on a cold night, that's what it's trying to pump up to the cam-shafts. They say (sounds a bit pessimistic to me) that it can take up to 10 minutes for oil to arrive in the rocker.
Anyway, until reinforcements arrive, the oil that sits up in the head has to lube the cam lobes and journals. If you overdo the revs, the oil gets flung off and ends up going back down the engine while there's little new oil arriving to take its place.
If the cam lobes get too dry/hot the metal "picks up" off the buckets... so you get scoring and a heap of metal swarf in there, which just makes things worse.
I guess if you had very bad wear you'd have poor running, possibility of knacking the crank or small ends (swarf) and probably seizing of the cams, followed by expensive and/or terminal cam-belt derailment.
Better just to let the beast get its oil circulating in its own time.