I should have probably explained my thought process.. I was meaning as though you only had, for example, 500 energy left and depending on your stamina you only needed an extra 500 to get the minimum 2000 actions for a raid, you might be interested in spending less dj/fp.
"I was just thought it might be use when you don't have alot of credits but are out of stamina or energy. But you still want to kill off a boss, enemy or get an achievement award."
The only problem would be that you would get penalised for this. If Kano did bring it in it would probably be 10 points for a full and 6 or 7 points for a half. The less you need, the more the fractional outlay would be.