If you change it to 0 seconds after making a change the browsers that have it cached wont see the change for a week. Querystring cache busting is great, we are a vb 4 site currently and I have made significant changes to it where almost all the the resources/static files are cached for a while but I change one variable and the cache busting kicks in.
I dont disagree with you regarding changing it to a week etc, I am more noting it would be a good idea if IPB put a cache busting querystring on it when they make the change to minimise headaches for others.