Hmmm
So there did not seem to me to be much to choose between PHP and JavaScript, because I am going to be forced to process one entire test section at a time, whether at my (server) side with PHP or their (client) side with JavaScript. If that is the case. I might as well use PHP and do everything at my end. Control, control, control!
When I referred to validating each item as being 'downright ridculous', I referred to requiring the candidate to first make a selection and then submit it. That would require, in the case of just one test section, 150 extra submits, and 300 extra packets back and forth between server and client.
What I am thinking of doing now, upon a form submit, is to validate and then, where necessary, generate a new form containing only the invalidated items. Messy for me, maybe, but clean for the candidate, obviously a "JavaScript free zone", and provides me easily with a key control feature - I do not want a candidate to continue to another section until the current one has been successfully completed.
Sound better?
I am very, very appreciative of your gentle guidance here. I want to use PHP for more than updating MySQL and I am not averse to dumping JavaScript - not in any way. But I did not want to find myself expecting to do what I patently would not have been able to do. Having just banished tables and gone to CSS strict for this application, I am not afraid of challenge, but everyone needs a candle in the darkness.
Again, my thanks to all for your thoughtful advice.
George