I think you mean the opposite advice of the natural reading of your text.
I read your advice as "Only use HTTP keep-alive if you have a high bounce rate", when I presume you mean the opposite.
1. Unless P, then Q.
2. P is "have a high bounce rate"
3. Q is "do not use keep alives"
I think you meant: 1. If P, then Q.
2. P and Q same as above.