I started doing machine laterals a while ago after seing them recommended here. My gym has a couple of decent (to me, at least) machines, Panatta and Cybex.
This may be a really stupid question, but: I'm progressing really well on the machines. Using something like 80 kgs/176 lbs depending on the machine right now.
Yet, I'm weak as a kitten on DB side laterals (maybe 8 semi-strict reps w. 15kg/33 lbs).
Why this disparity? Simply b/c the machines are easier and allow for more weight? Leverage (I've got pretty long arms)?
I know I tend to let my traps take over on laterals when things get heavy, and I guess more so on the machines than with DBs, but I don't really worry about that on the machines, since it hit the delts really well too.
So maybe I should just stop wondering about stuff like this and just be happy that I've found something that works well for my shoulder width...