I disagree that a few minutes of idling is bad for the engine.

It's winter here & I start my engine on near full choke, then immediately push the knob in untill the engine is running at about 800 to 900 rpm. At this point the fast idle function has come into play but the choke plate is mostly open & the amount of air being consumed by the engine is low enough as to be unafected by the choke plate.

I leave it run for a few minutes to allow the oil to penetrate all of the places where it is intended to go while the engine speed & engine loadings are low.

At this point the engine is actually running lean due to the temperature & you are right, a portion of the fuel arrives in the cylinders unvaporised, so it's in liquid form, however, at nil engine load, the manifold vacuum is at its highest for the circumstances, so maximum possible vaporisation is occuring.

Since my engine is a stock 1200 it uses the 'hot spot' form of manifold heating & this spot is heating up while the engine is running. It doesn't take long for some appreciable warmth to reach this spot & improved fuel vaporisation occurs within a very short time. The upshot of this is that with more fuel arriving in the cylinders as vapour, the mixture is starting to drift towards the ideal & rpm's increase, thereby creating more hot exhaust gas & heating the manifold even more.

This in turn also improves the manifold vacuum which in turn helps to improve the conversion of liquid fuel to a gas, thereby improving the air fuel ratio, which increases rpm, which heats the manifold & increases vacuum etc. etc.

I tend to wait untill the rpm rise to about 1200 to 1500 before slowly pushing the choke knob in & bringing the revs down to about 1000. This whole process takes only a few minutes at most.

Once I have taken the chill out of it's bones I bring the revs down to about 800 or so & select 'low' & drive up the moderately steep hill near my place at about 2000 to 2200 rpm. This allows it to climb the hill without upshifting & then struggling in second gear. The light throttle needed also means that manifold vacuum remains high & this combined with manifold heat minimises the amount of liquid fuel reaching the cylinders.

By the top of the hill & on the flat the temperature guage is already showing a reading & warmth is flowing from the heater, so I select 'drive' position & drive on steadily but normally.

The Jatco trans needs vacuum to control the shift points & if I drive off too soon, I need more throttle than normal, which results in low vacuum & higher upshift points. The cold oil in the trans, combined with the higher rpm makes for a harsh shift, particularly the 1-2 shift, so a little heat means a bit more vacuum & a smoother shift.
By using this method I have the temp needle right in the middle of the guage within 2k from my home which puts me at the edge of town, but of course the whole engine & trans are not properly warmed untill about 16k [10 miles] has rolled under its wheels & this is easily achieved as I can maintain an easy 60 to 80k in the rural roads where I live, increasing the pace steadily as the whole car warms.

So for me, a short time at a fast idle after a stone cold winter start makes a lot of sense.