The standard practice with hand brakes for many years was that they were the reverse in Britain of the standard in the US (left and right are swapped). I've seen DL1s in the US market that have regular US pattern hand brakes (my 78 DL1 has them), but I've also seen roadsters with the British arrangement (some Raleighs, and the modern Indian roadsters usually have this as well-- I know Eastman does). I guess it depends on the age of the bike and the target market for it.

I can't see from that picture well, but it is also possible your roller lever rods are crossed. Sometimes this happens, and usually you can tell because the brakes won't activate very smoothly. If they seem to be "crossed" then swap them. They should drop straight down from the rollers and not cross.

If your brake rods and levers travel smoothly and engage each other properly, I would leave them alone. If I recall, the rod linkages for front and back are different-- the longer link from the roller levers goes down to the front stirrup usually and the shorter one attaches to an elbow hinge on the front of the frame that in turn runs another rod to the back brake. I used to play around with them and found that swapping didn't really work.

"Pulsing" rod brakes can come from wheels being out of true, but usually happen when the wheel is slightly out of round. I found this out the hard way on one rim I had-- I had it trued up professionally because I couldn't get it to stop pulsing. It still kept pulsing. It turned out the rim was very slightly out of round-- I only noticed it after staring at the wheel spin for awhile; you could barely see anything of it, but you sure could feel it. Sometimes the rims can be adjusted professionally to get them back into round and true, but sometimes the rims can't be re-rounded perfectly enough to get rid of the pulse. I had to replace that rim-- I think the previous owner took it off a curb at some point. Rod brake are dangerous when the wheel is badly out of TRUE-- the worst thing is when the rod brake shoe goes into the spokes while riding. There is a ridge on the Westwood rim to prevent this, but if the rim is really bad, that won't save you. I would suggest getting the spokes and the wheels adjusted; it may not fix the pulse entirely, but it may help.