The FACT is that no court/tribunal/committee/body of law found Rajiv Gandhi's involvement in Bofors in any way. Just saying "everyone knows it" is akin to sanctifying mob-lynching.
I find it distasteful and shows the chinks in Modi's armour. I, for one, still feel that NDA will form the next government, but with such dialogues coming in, who is to stop different sides from bringing the other leaders' families into mention ? Where does it stop ?
For Modi, it was one thing in 2007 Gujarat elections to respond to "Maut ka saudagar" with the new coinage of words "Chaddarmod" and "Chenbhod", but on a national level, and at this point, it is under much greater scrutiny. Such dialogues aren't going to help BJP, and may even harm its prospects.