Is this a good blackjack strategy?

NO! You will lose early in the night and will be wandering around wondering 'what happened?' Here's why. What you are describing is the Martingale system and it is exactly as you describe...bet small, lose double, lose double, win go back to the original wager. Okay in your example you start with $5 and have a bankroll of $1000. First of all the bankroll you are starting with is about $5,000 too small. You bet $5, lose $10 lose, $20, $40, $80, $160, $320 now you are out of money. What if you had more money? You still could not continue because of the table limits will be $5-$300 or maybe $500max. What do you do if that $320 hand is a pair of 8s? Get a loan for the split, just hit it, or do you get scared and just stay against a ten? Do yourself a favor and just play with a standard progressive system of betting. Good luck!