I wasn't aware of this warning from Google, it's better to be safe than sorry - I should be more clear that robots.txt is not only for disallowing but yeah effectively, I've always included it by default as just good practice but I didn't know Google had become so restrictive. Guess now they have all the control, the barriers to entry must keep rising. I remember a time when you only had to put a page online and see lots of traffic. Nowadays with all the work we have to put into SEO it's almost like we're doing the search engines work for them.