... the printing mechanism, always lags a seq's evaluation ... (fastidiuos flounder)

[JuanManuel Gimeno Illa]

"That is, it won't print the first element before it has asked for the second."

I think the blame of these two evaluations is in the construction (loop [[x & xs] xs ....) that exists in the function print-sequential. The [x & xs] destructuring forces the evaluation of two elements of the original xs sequence. 

A simpler example of this, I think, would be:

user=> (defn spy [] (lazy-seq (print "*") (cons 1 (spy))))

#'user/spy

user=> (def s (spy))

#'user/s

user=> (let [[f & r] (take 4 s)] f)

**1

I hope this is the answer, but I'm not 100% sure.

Juan Manuel