Rod,
I agree with you completely. As I said in another post the remark was tongue in cheek.
Nevertheless, after flying 40 years most of which has been in the Midwest (IL) my experience is that under the SPECIFIC circumstances you described it would have been quite easy to descend into warmer air should ice have been unexpectedly encountered and once you got into above freezing temps whatever accumulation you had would have rapidly melted, TKS or not. That was the genesis for the post. As I said it was tongue in cheek and an attempt at humor, the point being that a plane can descend whether or not it has TKS, just pull back the power and/or push down the nose.
That said I agree that having TKS really does give you more options and a potentially greater degree of safety should ice be unexpectedly encountered.