Heya Madda, not flying the k-4 anymore? 
It definitely sounded like you pulled off the throttle right before the merge but he got the turn going a little sooner. With the excess speed it may have been easier to extend a little before turning in, either in a low g flat turn or some sort of pitchback. Hard to say sometimes but I believe with a bit of seperation and a slower speed you could force a remerge and would have been in good shape.
Yeah I'm still flying it, but there weren't many fights at first that night and I was flying generally poorly so I was screwing around with my second favorite plane.
I am complete agreement with everyone here that going nose low was where I went wrong. I had planned to go double immel after that short dive into him, but for some reason abandoned that idea.
Humble, lots of good info there and since I can't watch the film of it just now I'll have to re-watch it later tonight and digest a little better what you're saying. Great breakdown though, and much thanks. I did have him in view pretty much the whole time so losing sight wasn't a problem at all, though my tactics certainly were. I'm usually not so bad that I can't give even good sticks a pretty good fight, though I'll almost certainly lose. Just that night I was off a bit and lazer just really handed it to me in what seemed to me to be an effortless fashion. I thought I'd be able to turn it into an good learning experience for myself, so input like you're giving me is super helpful and greatly appreciated. Thanks to all you guys for your input. I've got a lot of thinking and film watching to do on this.