depends on the site you aim it at... if you target cnn.com with 70k of weight nothing's gonna happen. if you target a site you started last week, you'll draw some flags.
Yep kkibak pretty much nailed it, it depends on the site. An old site with strong older backlinks can take the hit more, new sites with hardly any age/natural backlinks can wilt and die rather quickly with the large unnatural link gain.
So whts the max weight I can use on a new site? Also, is it OK if I use 70K weight on diff links on a site. For e.g 15K on index page, 15 on an article etc.?
If the domain is new and its a new site I'd only use 1k in total with some deep links for indexing, certainly wouldnt use 70k at it unless I didnt want to see it again for hmm ...9 months +
I'd like to add to avoid confusion that it all depends on the niche. If it's somthing competitive like 'hosting' then the other sites in that category will be picking up links much faster than a uncompetitive term where maybe 2-3k of weight might get you to #1 on it's own. It's somthing you'll have to monitor and I'd be on the cautious side before throwing lots of weight at a site.