Opinions on the $TRIN?

Trading ES and YM, I've been using a sort of moving average crossover system for a while and one of the things I look for is confirmation on direction from the $TICK, $VOLD, and $TRIN in terms of the trend of each of these indicators. (If I'm long I want the trend of the $TRIN to be down and vice-versa for a short).

Today I noticed that the $TRIN was NOT confirming the moves but rather moving with the indexes. (It was trending down as the market was trending down).

I haven't noticed this before and it kept me out of 2 good trades simply because I was "in doubt".

Any thoughts on this from a more experienced trader would be welcome. Does this happen all the time, and I just never noticed it? Does anyone else use the $TRIN - and how do you use it?

I looked at the math and it makes sense to me that the $TRIN would move contrary to the indexes. If they are moving together, wouldn't money be moving into [an increasing number of] advancing issues as the market moves down?

Thanks.