Sorry for the slow reply; I've been a-travelin'.

Let me try the hidden-node-title technique here again. Steps in my test:

1. I created a new page with title "Testing Hidden Node Title" (without quotes). 

2. Per instructions, I opened the theme's page.tpl.php file, found the line 

<?php if ($title!): ?>

 and changed that to

<?php if ($title!="Testing Hidden Node Title"): ?>

 3. I saved the theme's page.tpl.php file and refreshed the test page.

Hmm, seems to work fine here. The test page is at http://www.drupalace.com/page_testing_hidden_node_title ; it now appears without title, at least for me. (Note: the title still appears in the browser's window bar at top, which is fine by me.)

If it won't work for you, I can only suggest the problem is perhaps:

a. Syntax error in your page.tpl.php file modification; or

b. You're modifying page.tpl.php file in the wrong theme (please don't laugh; I've done that sort of goof so many times); or

c. For some reason, this technique doesn't work with whatever theme you're using. (Any theme I'd know? FYI, I'm using my own Zen-derived theme.)

Can you test again and confirm that it doesn't work?