I've only done one no-secondary batch and decided not to repeat. It may be because my primary is in a carboy, not a bucket, but the krausen left hefty deposits on the upper, inside portion of the carboy. When I inserted the racking cane I couldn't help but knock some of these deposits off into the beer. Maybe it didn't hurt the final result, but I didn't like having it drop into the beer just before racking into the bottling bucket. Of course, as they (whoever they are) say, your mileage may vary.
Rick
Rick