I was just looking back, 5-6 years ago when Cross was mostly what we covered this time of year in cycling. Then, as now, racers may denigrate certain courses as grass crits.
Well, have a look at this grass grit from Belgium and the absolutely brutal pace, starting at 7:30 after a long intro.
The uploader, Cameron, gets dropped each and every lap, but drags himself back up to the group. Feeling how hard that is, I’d probably lasted at most a 1/2 a lap with that group.