Is there really a way to determine what all projects/coins will survive? I wish to invest now but I am really skeptical. Does the 'top 5-10' rule always work?Is it advisable to follow this rule blindly?
If you are really skeptical than let your skepticism do its thing - learn the project and the team thoroughly. If we are talking about altcoins with small cap that is the way to figure out which of them will got something to boast on on a distance and will show greatest results when bull market will come(because people will left useless coins to promising ones).
Or you can invest in top-20. They are "too-big-to-bankrupt". Diversifying will help. But don't expect fast huge return on investment in that case.