I think crosswind techniques should be taught before first solo.
Why?
I think back to my first few solo circuit sessions. Wind was nil at the time of being sent out, and about 15 minutes into the solo circuits the wind was around about a 10kt crosswind. I hit the dirt on a wide bitty runway on the following 4 curcuits - each time convincing myself that the next T&G would be better!
The 4th crosswind landing was supposed to be a touch and go but the landing was that bad it spooked me and I decided not to persist - and for the life of me I couldn't work out what I was doing wrong.
Now - bare in mind at the time many years ago at around 15 hours experience - I wasn't even sure what a crosswind landing was, nor had I even been given theoretical instruction!!
Had I have stacked it that day my career would have been over before it started (and perhaps the instructor's), and had I have been in a Cessna I might have been in a bit more grief!