I played against him a lot today, and couldn't even get the slightest concession, he kept beating me with more moves, and kept overpowering me - so I foolishly tried to counter with harder moves and more force. Which only led to both of us being tired out. In Randori week after week he continually throws me with Tai Otoshi, and I keep trying to counter it, but then he gets mad when I don't take the slap when he throws.
I think I need a new tack. Part of the tenets of Judo is 'Maximum Efficiency' or 'Best use of energy'. I need to get a little more cunning and mix it up against him, at least so that he doesn't get in for that throw.
I also need to prevent my adrenaline and frustration from getting the best of me.