I've tried it all, glueing, head cementing, pinching and crushing the stems.
The best thing is the follwing.

Measure the hackles so you find the tie in point., then do a couple loose wraps. You''ll likely find the are twisted in some way. Now, gently pull the hackles under the wraps. Once the fibers start to come under the wraps, they will straighten up like magic. you only need one or two fibers to be caught, this way the front of your wing wont be mishapen.

You can do this for pretty much any stemmed feather. I find it particularly usefull for tying the JC sides on salmon flies, but i've use it equally well for gp tippets, silver pheasant and saddles for rangeley streamers....