I am somehow sure, the market sentiment is driven by bitcoin price for almost all alt coins including Ethereum. A significant drop in alt coins on Friday was just a reaction of the dipping bitcoin price. Bitcoin price is dipping for a few reasons like scaling issues and uncertainty of a HF. Once there is a clear picture on the scaling debate, bitcoin will gain its positive momentum again.
Some other technical analysis by Goldman Sachs can be found here:
https://steemit.com/bitcoin/@shrirang/goldman-sachs-michael-novogratz-bitcoin-set-for-a-bull-run-to-usd3915
RE: Black Friday for cryptocurrency? May be not, but..............................