A 180 grit 4" diamond cup wheel like in this video costs $12 nowadays. I can give you the source if you like (import of course). So it does not make much sense to buy split carbide blanks for $11a piece (I assume they are imports too). Wearing out your diamond wheel is much cheaper. And they don't wear out fast. They can split many many carbide blanks and it takes only 5 min if you hurry it a bit.