Just out of curiosity, what time signature do most folks consider the walk-up to be in. I've played with a pretty good bass player who called a waltz, I personally like that and look for an accent on every third beat. Our drummer swears its straight 4/4 and counts it in fours but accents every third beat, which is simply impossible for me to keep track of - like 1 2 3< 4 1 2< 3 4 1< and so on....his point is with the middle and ending chromatic riffs it has to be straight 4/4 or you can't count it.
We rarely if ever nail it because the drummer never gives me an accent beat to shoot for.
He's more like 1,2,3,4,1,2,3,4, and so its like wish me luck every time! because timing has never been my strength, unfortunately!