I agree... but not wanting to start the whole debate on feeding live fish to pet fish, I'd suggest anyone who wants to do this read through some of the other threads on this debate. It might be "fun" to see your bichir eat a live fish, but you should be aware of the possible problems, and the advantages of feeding your bichir on dead and/or invertebrate live foods.
Seriously, I feel you should grow up about the whole feeding my fighter to my birchir issue, it would indeed be a slow horrible death and very painful for the betta concerned. Fish are animals, they live, breath and feel just as any other animal does, they're living creatures, life should be respected and valued, not tossed away like it's worthless. If you want to feed your fish to your birchir, (which I strongly disagree on) don't make a mockery of the subject as it's not funny, not clever and to be honest, stupid, pointless and barbaric. That's it for my rant. k'thx bye.
If we make jokes of our spouses, god and each other, then fish are fair game, if you ask me.
For the issue at hand, the betta will survive, initially, till the bichir is either hungry, or grows bigger, both of which have a high likelihood of happening in the near future. So no, it wouldn't be advisable.
If you want to feed that bichir that betta THAT badly.... STILL DON'T. I'll buy the **** betta from you before I'd let you do that They have bad enough conditions in LFS's. Don't put one through that.