Just outta the shower and cracked a beer after my first session on a race board. Thought I'd share some impressions while wife & baby still asleep.
Board: 2012 Cabrina LX - 188 x 69cm wide & setup in 3 fin mode. Proper race board.

First thought: How do I carry this thing? 70cm is too wide to tuck under my arm like a surfboard - and I have long gorilla arms. I could just about do it but hard on the fingers. It's about 500m to water at low tide, plenty of time to experiment with getting fin chops to the back of my knees.

So tempting to grab the base of a fin as a handhold, but I'm guessing that's bad for box/fin, so I avoided that?
Anyway, self launch Zeph 17 in about 8kts and head out deep.
Spent the next 1/2 hour trying to get up and going about 20m. Finally start improving slightly and I'm still up on the 2nd powerstroke. Stall the board on the fins and try to power out of it - end up launching a huge low railey which I land ribs first. Glad I'm wearing an impact vest - first thought "I'm gonna feel that tomorrow." 2nd thought "shut idiot I can feel it hurting now".
Take a break and it's picked up a few knots - perfect. A few more starts and I manage to go about 300m and I'm learing about TOES, pressing with the toes to flatten the board. Totally different technique.
Call it a day there, feel like a total beginner again. Am a total beginner again. Fun.

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Also thanks to Doycle for the amazing packing job, foam taped round all the edges, 3 box-in-box layers, and bright orange 'fragile' & "top load only" a4 sheets meant it arrived exactly as it left.