By 'rigor', do you mean the kind of rigor that is required to publish in journals like Risk Analysis or Minds and Machines, or do you mean something else by 'rigor'?

I can't speak for the original questioner, but take for example the latest post by Holden Karnofsky from GiveWell. I would like to see a response by the SIAI that applies the same amount of mathematical rigor to show that it actually is the rational choice from the point of view of charitable giving.

A potential donor might currently get the impression that the SIAI has written a lot of rather colloquial posts on rationality than rigorous papers on the nature of AGI, not to mention friendly AI. In contrast, GiveWell appears to concentrate on their main objective, the evaluation of charities. In doing so they are being strictly technical, an appraoch that introduces a high degree of focus by tabooing colloquial language and thereby reducing ambiguity, while allowing others to review their work.

Some of the currently available papers might, in a less favorably academic context, be viewed as some amount of handwaving mixed with speculations.