i'm thinking since it's an instead ability the following may occur:
enh is tossed (discarded from hand), but then goes to widow's table instead, which would effectively instead the toss ability meaning no decrease would occur
that's just my interpretation of reg 4 where toss and instead are defined as:
"A toss ability allows a player to discard an enhancement to decrease an opposing character in battle"
"The instead modifier allows an ability to replace one effect with a new effect."