That's backwards of everything I've ever read. If you deep stage you have less distance to move before you roll out of the beams, that gives you a quicker reaction time. Also, since you have barely started rolling once you're out of the beams the vehicle is travelling slower which would make your ET appear slower. If you shallow stage you're going faster when you pass the beams than if you shallow staged, which would give you a quicker ET.
Whoops, I totally worded that wrong. What I meant to say was it gives you a better reaction time. I was using "increase" as "better" which made no sense when I went back and read it. Sorry about that. Deep Stage is better reaction time and slower e/t due to the lack of a "running" start before rolling out. Thanks for pointing out my error. It was a long day yesterday!