I'd like to switch from a navigation bar (page 1, 2, ...) to a "show more" button. So basically the user will see only one page with a few comments and when hitting "show more" will have the next comments shown through some ajax calls.
But of course, if a bot looks at the page, I'd like the bot to see all the comments.
I'm wondering if this approach is risky in terms of SEO ? If not, what would be your recommended test to see if it's a bot or not ?
Another question is, if I get let's say 400 comments on a topic, how do you think a very long page compares to split pages using a navigation bar in terms of SEO ?