Well, they are your pistols, so of course you can modify them anyway you want and I would never say otherwise. People have been adding parts and subtracting parts from guns since there were guns, and they always will.
A little more on grip and why the tail is important to me.
Back in 2002 I attended classes at TDI in which John Benner and David Bowie taught me how to hold a pistol the proper way(combat grip, Leatham-Enos grip, high thumbs forward...whatever you want to call it) and that grip works. Is it the only way? No, of course not. Is it effective for fast follow up shots and overall gun control. Absolutely! That grip is taught in most of the major shooting schools as far as I can tell.
There is an article here about the "combat grip" well worth the read.
http://www.handgunsmag.com/tactics_training/combatg_100306/
Now, I used a Glock 23 back in 2002 for the 24 hours of training at TDI. (3) 8 hours classes over a weekend. I don't remember how many rounds were fired but I think the ammo requirement was 1,000 per class minimum or something close to that. You could of course shoot more, which most people did. I believe I shot around 4,000 rounds total in the 3 days. On paper, on steel, in the live fire house.
That Glock litterally wore my hand out. Here is a picture I found on the internet that best shows what happens with a Glock when the "combat grip" is used.
You can see on that skinny hand how the slide can get the meat of the hand right at the knuckle of the thumb. A little extra meat in the web of the hand or a larger hand(which I have) makes this much worse. You can look on David Bowie's web site and see that he actually adds beavertails to Glock pistols and this is why. He has been doing this since at least 2002 or before when I first met him. He was stippling grips at that time as well and at the time I had never seen anything like it.
When you have your hands high up in the grip tang of a pistol like shown above, it is liable to make mince meat out of your hand. Will it on YOU PERSONALLY? Maybe not, but I would contend that for a large number of shooters, it would. The gun companies know this, which is why I believe Sig added a line with the beavertail. Also why the XD pistol has more of a tail compared to the Glock and why the M&P has the tail. I don't think the reason is because they want to be like 1911 so maybe a 1911 dieahard will try one.
In the photos of the cut tails above, there is still enough there to protect the hand(I think) and the cut tails look like the tail on an XD.
I don't think the tail is there for anything more than comfort. Getting the hand high on the gun as close to the bore axis as possible is what controls recoil and muzzle flip. I can do that with or without a beavertail on ANY gun. It's just a matter of which is going to eat up the grip hand and which isn't.
It is THE FIRST thing I check on any knew handgun I buy. Can I get my hand up high and not get bit? If I can't, I don't even consider the purchase.
I own I think about 25 handguns. In that lineup are 3 Glocks(23, 19, 20) 2 XD's(.40 service and .45 service) and recently an M&P .40 full size. I've shot extensively and owned enough handguns to know what I want and why I want it.(which I'm sure others have as well and may differ from what I want)
Anyway, that's my story on the tail and I'm stickin' to it. :mrgreen: