Yes, especially if the person is adept at dodging it becomes real hard to hit of center spots. But if the person is a lot bigger than you wouldnt it take a lot of energy and strikes to make a chest strike work? When I spar we pound each other chest decently hard. It hurts but I can still go on and trade shots etc.
If I am close enough to hit them they cannot dodge me because I am immobilising their arms with trapping as I am hitting and putting forward pressure on them so they are off balance .
They can only dodge me if they stay out of range , in which case I will then chase them down with low kicks.
I would typically use the strikes I mentioned as a finisher , say for example on the end of a couple of chain punches. A double palm strike is very powerful and I can pretty much get larger people than me airborne and propel them back several metres.
The elbow strike is devastating as well because it travels in a circular action and then comes crashing down point first into the sternum breaking bones and caving it in .
Because of the way this elbow strike is done the force travels straight down into the body , much more damaging than a horizontal elbow .
Since you mentioned dodging , It reminded me of a drill we use to do to improve reflexes and footwork .
This drill will get you used to reacting to a highly mobile opponent and staying in our prefered range. Stand in front of your partner and start doing light chain punching on his chest make sure are in the correct range with your elbows bent .
Then have your partner dance around like Sugar Ray Leonard , get him to change directions and range constantly , he should be trying to get away from you and dodge you as much as he can .
Your job is to try and react to his direction changes and changes of range by trying to stick to him like glue , staying in range and continuously firing those punches into his chest.
The partner does not do any attacks , at this stage we are only working on being mobile in our stance , being in range and developing our reflexes in reacting to our opponents constant movement.
Probably best to do it for rounds of about 2 minutes as it can be quite exhausting , when you think your footwork and reaction speed is up to par then you can go back into regular sparring with you and your partner attacking and defending as per usual.