Of the thousands of bb defends I have made when the SB opens 3.5x + I'd say less than 5% have had a strong hand TTs+.
I defend my bb to 3.5x opens with all but total garbage, because most of the time this 3.5x open is an off suit Ace. Could be A/Q - which is strong - but I have just as much a chance at winning the pot with K/9, T/J o, 5/6 etc etc.
In other words - who opens 3.5x is nearly always overvaluing their hand - or trying to convince the bb to fold pre because they don't have confidence in their post flop play. Just my 2 cents.
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