Bits and Bitting

Yesterday at the end of the TTC there was a bit and bitting talk. The folks who did the talk were very knowledgeable and commented that horses who ride in hackamores were typically very tense and anxious. I ride Liberty in a s Hack and it's worked better than anything else I have ever used, but he isn't very relaxed and it's something I'd like to fix.  So, I grabbed the last unused bit and put it on a bridle for Liberty.It's a Myler short shanked comfort snaffle. It has the roller in the middle and doesn't collapse. It's a basic bit that I have seen horses use a million times. It took me a couple tries to adjust it properly but he was very patient with me. I got on him in spite of his nashing and gnawing at the bit and we walked around. I gave him all the rein he wanted, which was to take his nose to the ground (trying to drag the bit out of his mouth, silly horse)  I did like how round he was if I picked up a rein, but when I asked him to trot he was not regular at all and asking him to stop was frightening, even with a one rein stop.  So, I went back to the trailer, took it off and put his s hack back on.  He was immediately the horse I knew. He was steady in the bridle, light, responsive and didn't pull on me.  I then got Fiera and ponied her for 30 minutes. We averaged 6 mph, cantered, trotted, etc for almost 3 miles. Unfortunately it was all in circles in the pasture, so kind of boring, but I was impressed how good he was. We did some footwork after it and he did good turns on haunch and fore. I do wish he were more relaxed and I wish he could wear a bit, but I'm not sure how to force the issue. Maybe I need to try a bit with more tongue relief. It occurs to me that might be his objection...but at $100 a pop I'm not sure I will be trying another bit any time soon.