Norm Macdonald had a personal Twitter party tonight, recounting his experience on last weekend’s Saturday Night Live 40th anniversary show. The ’90s-era castmember and “Weekend Update” host fired off more than 100 tweets over two-plus hours detailing — fewer than 140 characters at a time — his role in the star-packed show that drew huge ratings. The snippets make for a great read, but the real takeaway was his admiration of Eddie Murphy.

Amid the tweets about writing the “Celebrity Jeopardy” skit was the SNL_Eddie_Murphy_as_Bill_Cosbynugget that, despite Macdonald’s pleadings, Murphy refused to do the Bill Cosby sendup in the sketch that Kenan Thompson eventually did. You remember — the Video Daily Double in the “Potent Potables” category in which an ugly-sweatered Cosby is seen mixing a cocktail. Imagine, especially in light of Murphy’s thuddingly unfunny appearance on the show, the roar he would have gotten by doing his legendary Cosby impression (see right). Might have been an all-time highlight. But, alas, as Mcdonald tweeted:

And why didn’t Murphy do it, especially given the battles he and Cosby had a generation ago when the elder comic legend scolded him for using foul language onstage? Here’s why:

Watch the skit above. Here’s hoping Macdonald gets a book deal out of this.