Tritone Substitution

So, I understand the mechanics of tritone substitution, however I am struggling with the "real world" application of it. I am particuarly struggling with using it when my melody has notes that become non-chord tones in the substitution.

For example, my chord progression is Bbmin - F7(b9) - Bbmin. Using a tritone substitution, that would become Bbmin - B7(b9) - Bbmin. The problem arising when an F-natural is in the melody from the dominant chord to the tonic. It seems like this would cause a nasty clash.

Another question: Does this chord progression make sense?: Bbmin - F7(b9) - B7(b9) - Bbmin

Well, if the F natural (which is in the key) is important as a melody, then I would not use the tritone substitution, unless the F was above the F# (which is also in the key) in the B7(b9) chord to make a major 7th interval (F#-F) and not half tone train wreck (F-F#), OR the F# was omitted altogether in the accompaniment.

You may have seen these

https://www.youtube.com/watch?v=oFUn6mQuq7s