Sort of broccoli

I saw that the rejects from the glossy kale/collard population were bolting and didn't want them to pollinate the select seedlings so I started snapping off the flower stalks. Hmmm... isn't this sort of broccoli anyway? Not quite as compact, but Brassica oleraea right? So I took the handful inside and cooked them. Well... I have to admit they were a little too bitter for me to say they were worth eating again - even with butter, parmesan and a big dollop of sour cream. So, if I hope to make a dual-purpose veggie - both leafy green and Springtime broccoli - I think it might be good to infuse some real broccoli genes (and maybe white-flowered Asian broccoli / "Kai Lan") to tame the bitterness. Or harvest earlier??? And not that I'd be eating the super-bitter ones anyway, but I wonder if the bitter compounds are the same ones [isothiocyanates(?)] that are supposed to be so healthy for us?