Yeah, do you recall their marketing talks when they
announced that their next Gen Pentium will reach 10 Gigaherz ?
It is definitely technically possible - I mean, they did sell a few machines with factory-overclocked P4EE's running at over 4 GHz. Add the fact that Netburst was fairly decent as long as you didn't try to use it for too many things (ridiculously large pipelines) and you have a decent CPU for video encoding and so forth.
Not that it'd be of much use today, when we'll just do it with the video card instead.
The problem with scaling was that the power consumption and heat emission was quite insane. Some of the later Netburst CPU's have been clocked extremely high, and it would be expected that theey could have increased speeds even further if they'd continued developing the architecture.
That being said, I'll rather stay at 2.5-3 GHz with a few extra cores if it saves power compared to a 10 GHz single core.
As for the 8086, I dunno. I'm not old enough.
