It seems to me that this fact dropping price of new tokens is closely connected with red market now. The author has called this topic as «ICOs in 2018 not same as 2017» and it is really so today even good projects with professional team and new idea sometimes cant reach hardcap. So this is natural and after the market begins grow again we will see in most cases how the prices after ICO increase in several times. But not today)
as for the authors strategy, it is really working and I try to sell all my bounty tokens during the ICO and then buy them in bigger amount several weeks later