Someone should be able to do some tests. What's the pull force required to deploy a reserve? Is it possible for a flopping reserve handle to generate that much pull force? Maybe a "fish scale" attached to an unused ripcord, at the point on the cable where it would exit the cable housing. Then fling the ripcord around a little to see if the force exerted at the end of that length of cable can generate that much pull force. If so, then a warning to a freefalling jumper might be in order. If not, then maybe it's best to ignore it, as you say, because you'll just get the jumper confused and worried about something serious, which really isn't much of a problem at all.