Of course your stronger on a machine, everyone is. But thats not a good thing or anything to brag about. Like they said about Smith machines it takes all your stabilizers out and lets you use all your effort to drive the weight up so yeah you'll push more weight, but you work less muscles. And on other machines they often use levers and pulleys. What levers and pulleys do simply put is take some of the workload off of the person lifting the weight, but in weight lifting that is obviously not a good thing because you want to be the one doing the work and using machines you wont really know the weight you are actually lifting. Machines definatly have their place but I think no matter what situation you name the answer is still going to be use free weights. (unless your hurt)