Looks like it. I originally had a Kalloy SC-201 clamp on the seatpost. It has the bolt 1-2mm from the seat tube and it didn't work with either of the two hangers I had. Managed to snap the bolt and ended up replacing it with a Forte clamp which has a little bit more space between the bolt and the seat tube. By that time I'd already slotted the seat tube in the back, so I didn't bother to check whether it worked any better than the original clamp.

Yours looks like a pretty nice design. More substantial than most and it appears to position the bolt further from the seat tube, which allows the hanger to fit with ease.