I haven't read all the posts so forgive me if this has been said.
I learned a few years ago how to shoot a straight on shot from 1/4 inch away straight on with draw or follow with no foul. I highly recommend practicing this stroke before attempting it in a match.
Adopt a very short bridge.
Choke up on your cue and close your back arm until you cannot move it forward any more. Completely compress your bicep.
Position the cue tip about 1/4 inch behind the cue ball.
Stroke medium.
According to physics you cannot push or double hit the CB as that your stroke can not follow through beyond center of the CB. It isn't possible.
That said, should you need to hit harder than a medium stroke, increase the distance between the cue tip and CB marginally.
Like I said, this takes practice but can be done. With a little practice you can even learn to play english and draw. Draw is tough because you must move so quickly.
I love doing this shot in front of refs. You can hear them about to call a foul as soon as you set up with a level cue stick...but a good ref is attentive and will realize after contact that no foul occurred. They usually want to talk to you about that shot after the match too.