If the bloom resets fast enough there wouldn't be nearly as many shot inconsistencies.
If you read Killa KC's post on his beta playing in New York he says "The DMR was single shot with bloom. However, the bloom reset much faster than the DMR in Halo Reach. I didn't have to pace my shots much at all. Both the DMR and BR were 5-shot weapons in this build. At the end of the night, I preferred the DMR. It shot faster than the BR, took the same amount of shots to kill, and I didn't feel like the bloom made me miss shots all that often."
You can have bloom without it affecting the shot hardly at all.