Just looking at the 1992 RM catalogue http://www.retrobike.co.uk/gallery2/...msmall1992.pdf,
the Blizzard is made from Tange Prestige tubing while the Equipe has Tange Ultimate Superlight tubing.

Why would they use the more expensive tubing on a lower level model?
The Blizzard had XT components while the Equipe had DX.