Two thoughts:
1) Sitting: If you're going to be a professional trader, you're going to have to bring a solid work ethic to the table. So, what happens when things start working? When things start behaving as you think they should? ACK! Nothing to do!! One of the most difficult things to learn is to not over-trade, not force a trade, or as I glued it into my head: SIT ON HANDS. It is very hard for a good trader (one with a work ethic) to S.O.H.. But clue: If you give it a stupid name (like, "S.O.H. Angst" it will be easier. It has an identity.)
2) Broadening: While I agree with the idea of sticking to your particular product/technique in order to shine, shine, shine, there is also the idea of "always having another [and fundamentally different] iron in the fire" because as qxr1011 wrote, "at some point in the future your method will stop working and that will be the necessary kick in the butt (necessity is a mother of the invention) that will push you to improve the method (also, not necessarily you will be able to do that)."
I used to scalp equities, then ES ticks, then did some index credit spreads (at a time when you could mill 2% from the market week after week, and vol<11 or 12 was a headline-maker).
As I got better, and the market got tougher, I had to "invent" trades to deal with shit vol. -- my thoughts went from positions to the entire inventory -- then to inventory (portfolio) management, then back to trading statistics almost like for scalping, then a really *detailed* study of the sold Risk Acceptance of the credit spread against the Premium Received of the reward end of things....... This past summer, I ironed out conditions for *me* to actually BUY

some long positions via calendars. But that's what week after week, month after month, of sub-10 VIX, or even-and-by-Gawd, sub-8 VXST, and the *laughable* effort to even pull 1%

from the market each week, will do to you.
Always be a learnin'.
Always be prepared to recognize when *not* to trade, and be willing to recognize Your Inner Trading Awesomeness, and SIT ON YOUR DAMN HANDS.
And
Please! don't ever force a trade.
"Capital Preservation" over all else.