Just did my rcr coures a couple of weekends ago, we did not manage to get a single windscreen out!!!
We got told that we should tru to work around it, unless it is a H - mould, where you can just cut it out with a stanley knife.
If it is one of the ones that is glues in you can sometimes cut around it with a draw knife, but it is rather time consuming. and if the glue covers too much surface area, you amy need to use a screw driver to finish the job.
When working around it, the best way to do it is with a forward roof roll,
(cut B, C, D pillars, relief cuts both sides 10cm back from A pillar, and fold forward using crowbar to make crease in roof.)
or use an a-pillar lift to free legs from entrapment. (cut throgh Apillar complety just above sill level , cut a-pillar again just above dash, cutting through windscreen, open bonnet and cut relief cut in fender "c channel", cribb under sill inline with a-pillar, spread lowest cut on a pillar so as to lift the dash up and out of the way)
just remember your soft and hard protection!!!
One good way is to just avoid it completely, just cut all pillers including the 'A' piller and fold the roof forward on the windscreen and it will usually just pull out and you can then take the roof away windscreen and all....
just my opinion, but i would prefer to go for a forward roof roll... less chance of roof being drepped on casualty/ambo/anyone, same number of cuts, and windscreen remains in tact, obriously it may be impossible if it is car vs tree/ stobie head on, but in that case i would still prefer to halligan across the entire roof to keep the screen intact