I know others who dismount their bicycles in this manner, and, like me, they find it completely natural and intuitive. But I've also been criticised for this move. A couple of people have told me that doing this to the bike repeatedly might distort the frame. Others have expressed concern that one of these times I am bound to get "tangled in the bike" while swinging my leg over. The latter does not really worry me; my body seems to have an inherent awareness of where the top tube is in relation to my foot. The frame distortion idea is intriguing, but seems far fetched: Can the sideways jump really exert sufficient force to twist these tank-like frames?
I never set off to adopt this style of dismount; it just sort of happened. As I kept raising the saddles on my city bikes higher and higher, eventually I could no longer reach the ground without leaning the bike to the side. The "slideways" move was the natural outgrowth of that: Somehow I find jumping off in this manner easier and more natural than the typical method of standing up on the pedals and then stepping down. At this point I've been doing it this way for over two years, and it would be a difficult habit to break!