Hey @SteveMika just wanted to +1 @toogdog here that the adjacent tone usually is pleasing.
BTW - the term harmonica players use for this is PLAYING DIRTY. A “dirty note” is when you let a little bit of the adjacent hole (often, but not always, the hole to the right of the main melody note.)
This is one of the wonderful things about our amazing instrument.
BUT you’ll notice one avoid place is where the notes switch from draws being higher pitch to blows being higher pitched, that is the -6 and -7 played together sound like an alarm clock (the interval of a major 2nd is very dissonant.)
So, I recommend trying the pitch to the left or right of the tabbed note and seeing how you like it.
I also like to try split-3’s and split-4’s, but if you’re talking about more Dylan-esque stuff like what @bjdas is referring to (and thank you for your kind words @djpas!) then no need worry about splits - it’s all just adjacent notes on the harmonica.
But for anyone whose curiosity is piqued about splits, I LOVE 'EM: