I don't know if this is helpful, but a couple of years ago I found that Netscape and IE (both under Win32) were choking on a form that was quite complex and long.

Testing showed that if the amount of data in the POST exceeded 64K, the browser would hang. We were unable to reproduce this under other OSes (FreeBSD and BDS/OS at the time).

I assume this is not the case nowadays, but my advice is for you to do some testing before going ahead if your text is that large.