Not sure why. It's not crazy compression and it will bleed off plenty of cylinder pressure at lower RPMs. TIming will be key. Most guys have too much timing and way to fast of a curve for street use.
This is incorrect thinking. Nothing is "bled off" as you say. The later intake valve closing simply makes compression start building later than an earlier closing event. Nothing is lost or bled off, the cylinder simply begins to make compression later in the compression stroke, therefore less compression pressure is made.