and what is the cause when 3 link pages of my site blocked in google tool bar and vanished from google index - reciprocal link?? 3 way link???
Google always playing with SERPs. if you dropped dont do anything yet but wait for few days to see if it will returns. if you go up, think what you have done and do more same strategies.
Hahaha That would be too simple and i would call you genius!! Google is much more complicated than that. Alot of sites with hundreds of backlinks have all the sources linking to them!!!!!!! But they still fall in SERPs! My site can stay stable for a year then drop for 2 days, reappear for a year and vanish completely from SERPs for a week. But most of the time i am stable. Unfortunately you can not explain heavy drops say from 1st page to 500! Google itself doesn't explain it.