I don't know that I'd call that overreacting. That's pretty much exactly what I do. I don't like it when he's under 50, and I'm not thrilled when he's in the 50-70 range. Those are totally safe numbers, but I don't trust him to stay there. He gets 15% or 20% carb food if he drops low (below ~50). But it's also a combination of the actual number and the rate of change. If he's in a steep drop, I'm more concerned, but I know that I can pretty effectively put the brakes on by giving a bit of carb. If he's in low numbers and staying there (once I put the brakes on), I'm less concerned but still keep an eye on things. My testing frequency depends partly on how fast his BG is changing. (I actually have a separate data tab in the spreadsheet I use to do the rate calculation for me.) I test frequently enough that I can usually catch him before he goes really low, though every so often he surprises me. He's a master of the epic swan dive.
