Lionelt, I strongly agree that we need to be mindful of WP:WEIGHT when it comes to Boswell. I've argued this for years, as you can see in the archived discussions. However, considering how much traction Boswell's idea has gotten - virtually every work on Sergius and Bacchus that has been printed since discusses it (very often criticizing it) - it does need a brief, neutral mention here. I believe that the stable version of the article did that - it indicated what Boswell said regarding Sergius and Bacchus, and then noted specifically that other historians have criticized his methodology and interpretations.
There is no need for a point-by-point evaluation of all claims Boswell makes regarding Sergius and Bacchus (additionally, not all those claims are disputed; for instance that Sergius and Bacchus were the most popular example of paired saints). Indeed, WP:FRINGE specifically says not to do this. It is enough to indicate that many other historians have rejected it. t/c