Not to burst your bubble, but since someone has written a book on pen turning and uses epoxy to glue in parts, they're doing it because they've made a lot more pens than you and there's a darn good reason for it. There is most certainly a good reason for it, which is that if you want your pens to last in the condition you sell or give them to someone, then certain parts, especially on certain kits, need to be glued. If you use CA, make sure it's a thick gel CA b/c a thin CA might squeeze out when you press the parts together and it's a beotch to get it off the hardware. The bad thing about using CA to glue components together is that CA 'off gasses' for 24 hours as it cures. What this means is if you are gluing the clip and finial on a screw-cap pen, you have to leave the cap off the pen for 24 hours after assembling it, otherwise if you glue and assemble the pen and just immediately stick the nib end into the cap, the off gassing will leave a chalky white powder on your nib section that's a nuissance to get off, especially if you're doing 100 pens at once, DAMHIKT.
Because of the messy squeeze-out and the off-gassing, epoxy is the preferred method of gluing parts during assembly. Once you've been making pens for a while and you've tried all these different things for yourself, you'll see that things like gluing in parts do take longer but result in a better end product, which is important for your reputation if you are selling pens on a long-term basis. But if it's $12 slims you're selling at a flea market or a gift for your 10-year old niece, don't bother gluing.