I can't imagine 2 mg from 3 days ago, even if you take 2 mg daily for a long time prior to that, is doing that much to block the high.
But yeah if you are use to 2 mg of Sub I could see 70 mg of hydro not being the most jaw dropping experience. I would think you would still get decently high off it. Did you do a CWE? if so maybe a lot was lost in the process. That was the one thing I hated about hydro, can't get it without all that APAP and I hate not knowing how much I lose doing a CWE. Still was a better idea than eating like 3 grams of APAP.
I also found hydro a lot weaker in comparison to oxycodone mg:mg, like a lot more than the supposed 1.5:1 ratio. This is before my tolerance required a CWE, when I could pop a few percs/vics and get a decent high. I would rather eat 2 5 mg percs than 2 10 mg vics.