At the bottom of the page, there is a link to enable advanced functionality. I'm not sure of a way to make it permanent.
That's great, thanks. I hadn't noticed that.
I use a chrome 'search engine' to open blockchain.info at particular transactions. The string I now use is:
http://blockchain.info/search?search=%s&show_adv=truewhich seems to automatically turn advanced mode on each time.