Many ways exist to see your posts. Its true that by clicking the "View your posts" button, you cannot see more than the last 100 posts you made but you can still search and view your old posts using the Search tool.
On the right upper corner of the forum tool bar, you'll find a button that says "Advanced Search". Click on it. The click on "Search Single Content Type" Now, select "Posts" in the search type. Then enter your username in the search for area, where it says "Username". But here comes the trick. If you click "search" at this point, you'll view your last 100 posts. However, if you want to see posts older than that, in the advanced options area you select "Search Forums" and select either All Open Forums or whatever the subforum you might want to search in. Then in find posts, you select the period of time you want to search for your posts. Example: At least a Year and Older. The more you can narrow the search by searching only in a given subforum, the better the search results will be. You can even put the search to show its results in threads you posted in, so as you can get 100 different results, instead of 100 results which some might be posts in the same thread.