actually funnily enough within the span of a few months calgary made two trades with st louis, for similar reasons.
one was (arguably) the wrong move: rookie brett hull for veteran two way dman rob ramage and mike vernon insurance (rick wamsley). arguably because longterm, or even short-to-medium term, that was too much to pay.
the other was the right move: bullard for gilmour.
but it was the same gamble and both contributed significantly to the 1989 cup. slow, all offence/no defence guys with questionable competitiveness swapped for tough, playoff hardened players who took care of their own end of the ice.
but obviously hull was so good, he succeeded (wildly) anyway. and i think this was really hockey IQ more than a really really excellent tool (his shot) that made the difference between a hall of fame career through the DPE and being scoring winger the game would pass by in the early 90s, say a rob brown, who also was a rookie in 1988.
when hull was in the lineup that year, calgary had a an unbelievable third line: bullard centering hull and tonelli. a current 100 pt player with a past and a future one. the other lines would be rookie nieuwendyk and roberts with hakan loob, and otto centering mullen and peplinski. with tonelli leaving in the summer to be a ringer on the LA gretzkies, that entire third line would be gone by the cup year.