Hey guys, I've got some money sitting in a savings account making low monthly interest (well below 2%) so I thought I'd invest in some bitcoins instead

I remember hearing about Bitcoin when it was first released and loved the idea but didn't have the funds to play around with it back then...Now I do. Anyway, I already have a long time friend who is in the bitcoin buying/selling/trading "game" and that is really all I am interested in as well. He strategy is something like this;
1) He buys bitcoins on Circle (from a U.S VISA debt card tied to U.S Bank account) when price is low
2) Holds on to them until price rises (from Circle, he transfers them to a wallet on his local PC for storage, Electrum)
3) After price goes up, he sells them on Localbitcoins
4) For example, in November he bought 5 when price was ~$280....Sold them yesterday for ~$420 each ($700 USD profit in 30 days)
He pays very little sending/receiving/converting fees along the way and everything is almost instant he says, and relatively safe. Any thing wrong with the above? Any better suggestions?
I'm not a U.S citizen but I do have a U.S based bank account and debt card so only want to buy them with USD funds I have on there...No paypal/gift cards/etc. No dealing with chargebacks, invalid codes, etc. Aren't bank transfers the best option anyway?
If it does work, everyone would be rich. The main problem here is the risk. Bitcoin doesn't always rise, it can fall too. If it does, you would suffer huge losses. I'm sure that they at least need a simple ID verification for using their exchange.