It appears to be host/server specific. Some hosts are using mod_pagespeed quite aggressively and this is creating problems dealing with minified javascripts. The fix you applied stops WP from minifying the scripts.
Oh… OK. So, should I leave it that way, with define('SCRIPT_DEBUG', true);
enabled in wp-config.php?
For the time being, yes. The only other thing you could do in the meantime is to contact your hosts and ask them about mod_pagespeed and its potential effect on minified javascripts in WordPress. They may want to adjust their mod_pagespeed configuration in the short term if they host a number of WordPress sites.
The host says it doesn’t have mod_pagespeed enabled or configured. Any other ideas?