This is because the JComments form doesn't display (by default) when the comments won't be displayed. So if you aren't displaying comments on the front page it won't show the form. The 'add comment' button on that page is technically different then the 'add comment' on the article page for this reason.
Thank you! And how can i set joomla to show comments on the homepage, please???
If i go in the backend /menu/main menu/home i can't find an option to set to show commens...I can find to show or not icons, links, categories, etc. but not comments!
Can you help me please?
Thank you