It's an interesting twist to an old story. I hear the self signing for the first time.
While I think the self signing is a potentially good way to avoid trouble with avirus companies (and if you could run a posteven in lazarus , relatively painless), that is only one side (the avirus company's). The "everything is already signed" is total bogus IMHO. Only end-user software is signed.
The thing they don't say is that generic threat detection is the cause for the bulk of the problems. In corporate virusscanners this is disabled, and those only react on signatures (since any follow up will be done by expensive staff, and there are too many false positives)
The consumer based antivirus circus however is based on a fear, and a notification sometimes (even when false) gives the consumer the feeling the product "works". And it's always the low end end-user products that give the false warnings (avira specially). I suspect they are big on generic functionality because their organization is simpler and can't afford as large invests in the signature scan as the big ones (mcafee and norton to a lesser degree, these write that off on the corporate market)
In general we standardly advise to either use a corporate version (great argument if the customer bangs on about "professionalism" and he turns out to use a consumer product), or to disable generic detections on systems that run custom software.