Yes you should. You want to hold productive assets (stocks) in an ownership capacity so as to take part in their earnings.
Currently, you are doing so by hiring FA guy (1% fee), so he can put you in his favorite mutual funds of the day (0.5-1% fee), which then purchase the companies you are trying to own (Apple, Google, Whole Foods, British Petroleum, etc. etc. etc.). That is 1.5-2% in completely unnecessary frictional costs. 1.5-2% is not insignificant, it's 1/4 of your expected long-term return!
Instead, you could buy Vanguard index funds (0.05% fee) in order to have the same ownership in these companies.
There's really only two reasons to keep FA guy: 1) You need the hand holding to stay invested in the market because left to yourself you will market-time, panic-sell, etc. 2) He is providing exceptional planning expertise you would have to pay an equivalent amount elsewhere to get (taxes-CPA, social security, insurance, etc). Again, even with 2), you can and should be learning about this stuff yourself, or it isn't hard to hire out on one-time basis if badly needed.
Finally, the SP500 had a total return in 2015 of 1.28%. If he returned -15.9%, he is taking on an unreasonable level of tracking error, and uncompensated risk. That is obscene under performance for a FA, but also not surprising.
I work at an Registered Investment Advisor firm in the investments and planning groups. Good luck.
EDIT: Oh, and as a poster above mentioned, you're not selling at a bottom or w/e. You're simply allocating the same holdings to a different custodian (FA guy to Vanguard). You will own a relatively similar (or most likely improved) basket of stocks.