Growing up with Spidey.. I kinda agree with Slott here. Moreover, the big crossover events like Secret Wars/Infinity War/Gauntlet, I always treated as alternate universe side stories, Marvel borrowing Spidey for their big events because he was their biggest icon. I never thought of those stories as canon to Spidey's more personal, mainline series stories. (Personally I regarded Amazing as the only canon series of Spider-man stories, and Web and Spectacular also as alternate universes). So if there was any killing going on in those alternate histories they never affected how I understood the character. Bringing the symbiote into the Amazing Spider-man universe did blur the lines for me some, but still, Peter Parker from the Amazing storyline is a guy that wouldn't kill unless pushed to the absolute extreme -- it would have to be so personal a case (like revenge if Mary Jane died.. and maybe ONLY in that case) that ultimately it would break him psychologically as a character forever. It's just not in him.