It makes sense to have a lot less details on a front page. The users have to be able to take one look and gather most of what your client has to offer.
Hiding content it's pretty useful... until the first click to reveal it.
If, upon users action, the revealed content would go past 10 rows, that will also intimidate users.
Even more, by revealing one large piece of content they also might get lost in the page, since that's a pretty big change in "scenery" and users may not find their "way back home" or they will also have to scroll now.
So, it's more about how large is the largest piece of content you have hidden.
Keeping a whole lot of content in one page doesn't make sense since a long time.
In your clients case, you either implement "short topic descriptions page - longer fully detailed page" couples or go for extremely well designed, meaningful and condensed billboards.