I'd rather it be easier to bookmark and go to a different unshuffled playlist rather than contaminate my shuffle

Point taken. I don't have that problem because I envision a different use for it... I don't mind contaminating my shuffles.

An example of a way I would use an "Insert Sequential" feature is like this:

- I start a long road trip.

- I have Shuffle turned on (perhaps one of the weighted shuffles, perhaps not) and I do a down-down-down to get all my tunes going for the road trip.

- During the road trip, I decide to listen to one of my backlogged CarTalk episodes (I grab the streamed episodes from their web site each week and put them on the player in a special "CarTalk" folder which is Ignored-As-Child. Essentially, I'm timeshifting their episodes. Each episode is ten sequential tracks).

- Right now, to do this, I would have to turn off shuffle and play the cartalk episode. Then when the episode is done, turn on shuffle and do down-down-down again. I could just turn off shuffle and insert the episode, then shuffle again when I'm done, but that would run the risk of getting bits of the episode mixed in with my music unless it was on a weighted shuffle.

- With an "Insert Sequential" feature, I wouldn't have to turn shuffle on and off. I would simply leave my main shuffle playing, insert the CarTalk episode sequential, and forget about it. The CarTalk episode would play properly in order, then my shuffle would continue where it left off.