Diversification
Finally for those of you who do not believe, there is a rather large amount of data available about single or double engine shutdown incidents at high altitude. Most of this is assumed be due to ice particles, but some may also on ash or mixed ice/ash particles.
Where does this extrapolation fit into the discussion subject
It's already known what ice crystals can do on their own and where they are likely to be encountered so as to avoid.
Likewise it's already known what certain types of encounters with VA can do and how best to avoid and/or cope with it.
The two are not the same as far as the engine is concerned nor have they ever been linked together.