I think I've only used the tunnel like twice in my whole life. It just felt strange. I never stick my dick through the pants hole either, I already feel like I get to much zipper on skin action with the over the top method and the dick through pants hole thing always seemed way worse in that regard. It probably doesn't actually make a difference but I also feel like dick through the pants hole makes it more likely for me to pee on myself.
That said the over the fence method is not without its perils. I seem to recall losing the grip on the elastic of some of my tighter shorts midstream which obviously did not go well afterwards. Its only happened a couple times though.
do you over the top weirdos not wear belts?
I always wear diapers with belts so I don't have to redo them every time I pee so this is a moot point. Its the only way to do it really since we all know buckling a belt takes at least a half hour to do correctly.