Ive never had to fight him, but you got me interested and i pulled up alot of websites and read my *** off about how to fight with him and his weaknesses and stengths.
Ok first of all, attack low, he cant block low well. Dont use combo's he can block rushes well, use fast and one hit attacks. Whenever you see him falling backward attack low. Though he has a low block which he can recover from fast and is very close to the oppponent, so you could try use Lei and nail him low, drop to the ground roll backwards and pull up into snake or something fast, not crane, kicks are to slow i would imagine. Dont use grabs, he can reverse pretty much everything.
The minute you see him dropping to the ground, jump, cause he is likely to do some sort of rolling attack, he is good on the ground, try keep him up. Never get to close or he'll burp on you. So after an attack pull back quikly unless he is loosing his balance which i suggest you attack low again. Also if he sparks and tries to jab something into you jump and nail him. Also he has two attacks in which he falls over afterwards, one can be identifed because he sparks and then start falling backwards, try get him then aswell.
i pulled this from a website, read it right to the end, it tells you a bit. Especially the bit in brackets at the end.
"Reversals, Parries and Auto-Reversals
To do a parry with Dr. B, press S+T. It only works against high and medium punches. For a low parry, press d+S+T. This will dodge any attack that hits low, but it will not actually parry it or reverse it.
The effects of either one of these is marvellous. Firstly, if you parry a high or medium punch, you have three options. The first is to perform a grab by pressing S+T. This initiates Dr. B's excellent multipart throws. The second option is to press X+O and go for a crouching throw. This is useful if you delay very slightly and let your opponent think you are going for the standard throw, as you will nab him as he tries to duck the grab. Not as powerful, but you get a cool soundbyte. The third option is to do nothing. After a while, you will flash electricity and be momentarily stunned, but until then you have a medium to high auto-reversal shield enabled. If your opponent tries to hit you between the time of your parry and the time you spark, his attack will be automatically reversed (If you are playing against Dr. B and he does this to you, remember that Dr. B's reversal is nothing special, you can chicken it too. This is very nice to remember as you can force him to reverse your attack and hit him with a free chicken!)."
thats all i kins find for now