When the promoters and advocates of cycling and things like BTW start to realise that there need to be training programs attached to all of it, there might be some sign of success.
Unfortunately, there is an assumption in the community that if you run things like BTW, people "naturally" know how to ride a bike, and are properly equipped to do so. The post immediately above this one shows this to be a lie. The posts from newbies on this forum do likewise.
I am heavily critical of many of these types of promotions, particularly those promoted by green organisations, because they pay scant attention to the needs of inexperienced cyclists, and are serving needs other than those of the cyclists -- that is, to push political propaganda agendas.
Riding in traffic is *not* an innate skill. It requires learning and testing and experience. People who jump straight into it without training end up telling all and sundry about their bad experiences. Those bad experiences put off way, way more people from ever trying to cycle-commuting as a reasonable and viable long-term transport option.
People also are embarrassed or unwilling to say they don't know how to deal with riding like this, because of this attitude that they know how to balance and turn the pedals, therefore they are a bike rider. When promotions such as bike-buses or bike-trains are introduced, they get minimal support, or fall by the wayside because no-one cares about the newbie, or people are afraid of being shown up for the deficit in riding skills. Or their riding behaviour and habits are such that they regard those behaving appropriately as not worth their attention (ie, they behave really badly and put themselves at risk, and think good traffic cycling is stupid).
If you take a hard, critical look at it, the average city where you might want to promote an increase in cycling as a transport or commuting mode, the cycling base will be way less than 1% of all current trips (bus, car, walking, bike and whatever else) and you might be lucky to get that to 1% after a BTW promotion city-wide.
Plus, these promotions suffer from the wham-bam-thank-you-ma'am syndrome all too prevalent in cycling promotion... a single BTW day or week out of 52 doesn't keep it in the eye of the public -- for many people, it is regarded as a weirdos day out. And the money supporting it disappears pretty rapidly. The companies and governments that do support it should be offering that support over 52 weeks a year.
The only programs that I have seen that have been successful are two in Australia that require the participants to undergo fitness and competency training, sign and agreement to ride a certain amount of distance and time for a year, and provide them with a bike which they then keep at the end of 12 months if they complete the agreement.
There are 25 riders out there right now in my area that would not be commuting unless the program -- a joint venture between government, cycling advocacy, employers and employees -- had been put in place. There are another 100 or so out there as a result of a similar, larger program in another city.
Conversely, I can recall only one individual taking up and continuing cycle-commuting because of any other commuter-specific promotion that has been undertaken in my area.