Just thought I'd post a quick note to say that there was a similar experiment in England a while ago.

An experienced touring cyclist went out in his normal gear: no helmet; ordinary clothes etc. Then he went out again in helmet, luminous jacket and all the safety gear, and found that vehicles gave him a lot less room when overtaking, pulled out in front of him and generally gave him much less respect. He took it to be because other road users took him to be "safe" and so didn't have to worry about being respectful.

He then went out in the cycling policeman's uniform. He had no trouble then!