i am using a software to find related blogs to my category and niche, and will be collecting all PR1+ blogs and post comments with a link to diffrent articles on diffrent directories, and i should rank for those article pages pretty good from several high PR back links, and from those article pages i want to link to my site. question, how many diffrent article directories should i use and how many same comments i should use on 1 high pr blog? also except of buying links and submitting to high PR directories, what other type of methods i got left to have high strength pages pointing at my articles? and how much of PR3-4 pages should bring my article page to strenth 4?