I have taken the idea of mixing caprylic acid in shakes a step further and used raw apple cider vinegar (1 tsp.) and it was surprising how much easier the shakes went down. And the raw apple cider vinegar has benefits for your body. It is an anti-fungal because it turns to malic acid in the intestines which prohibits the growth of candida (or so I understand). Another time I got wild and crazy and mixed in a couple drops of Oil of Oregano because it is anti-fungal,bacterial and viral and I thought it would really get pushed into my intestines this way. It definitely changed the taste of the p&b shake, if you like Italian you might like this.
Ultimately the best tasting product I have used is Flaxium by Bio Active Nutrients it has flax and psyllium mixed together and it had an almost sweet taste to it. I really liked this product but due to finances I had to go with the plain stuff this time. You can find more info out about it at http://www.bioactivenutrients.com - I have no ties to the company, just have seen it advertised with Your Health with Doug Kauffman, a show I like to watch.
What about mixing in some fresh lemon juice? I haven't tried it but it sounds refreshing to me. Oh and try to throw it to the back of your throat while swallowing it, I try to avoid the front of my mouth with it and keep it going straight for my throat.
Hope you can keep chugging the p&b the benefits far outweigh the nasty taste :o).