According to some analysts, the yield curve control that Japan is resorting to is basically a type of helicopter money only. That is because this strategy lets the government spend more without having to worry about bond yields jumping.
BoJ, however, rejects the allegation on the basis that the "BoJ still buys bonds from the market and does not directly underwrite debt from the government, something that could undermine confidence among investors."
The line, however, is blurred as BoJ buys roughly the same or bigger amount of bonds issued by the government.