The only evidence I have Bernard is the continued operation of such set ups over the last few years without problems. As mentioned you can test wether it operates properly before deciding to fit it as the sensors indicator light lets you know whether the set up will work or not at the time of fitting.
There appears to be no deteriation over time.
Lack of knowledge again.
To be fair, you said in another post it is caracter assinagation. No, its pointing out you fit what comes in a box.
And have not a lot of ideas as to what it does.
Challange for you, work for a acredited alarm company for a month. See what you learn! I bet you gain more than they do!