The $20,000 prediction is a safe one, assuming price developments of the past remain valid for the future. But it takes only one bubble to shed that safe $20,000 projection to pieces.
Looking at
the BETI indicator, we have reached neutral zone now. A 2013 repeat would mean $30,000+ That is not impossible, especially if we are nearing the point of 'crossing the chasm'. With marriages of fiat and crypto rolling out (e.g., TenX, Bankera), we may be less away from this point (the chasm) than we think. Crypto is definitely a HODL for me toward 2020, no matter what (except the BETI indicator reaching 1.5 before that).
Accumulate, HODL and prosper.