Hiya!
Do you do the same with ability score increases? If a character takes a +2 to Dex and thereby a +1 to AC, do you automatically up the to-hit bonuses of all all monsters? Increase the AC by 1 to negate the to-hit bonus of the PC?
Nope. Why? Ability score increases are not OPTIONAL, like Feats are.
I mean, obviously, monsters faced will get tougher as players level up, either because the DM always runs balanced encounters, or just because the PCs will get bolder in the opponents they're willing to fight. But the feat is just a sharpened version of the ability score increase. With a +2 in your prime stat, you get a little better at most of the things you do. With a feat, you get a lot better at something that you do sometimes. If the game is just allowed to function naturally, that player will feel the benefit of that feat in those specific situations, but also feel that their stats might not be keeping up as well as they face increasingly challenging monsters.
(I'm a fighter and I get this really cool -5/+10 thing with my Greatsword, but the monsters are getting better armor and I still have a 16 strength...)
I've said this in other threads and whatnot back when we were still playtesting 5e. My contention was that I didn't want Feats to have the "...but this one goes to 11..." mentality that most of the Feats from previous versions of the game had. Yes, there were a lot of feats that didn't just grant "bonuses", and those were ones that nobody took...and if you did, chances were that someone you play with or might play with would get all pissy because of "
stupid choices for feats...now you suck and my character has to pull up the slack!...grumble-grumble". It's easy to find examples of people verbally attacking other players for "stupid feat choices" all over the place.
How Feats
should have worked was a LOT less "+1's", and a lot more "here's something cool you can do, or reduce, or ignore". For example, GWM should drop the -5/+10 and replace it with something "non-pluss'y"...say, give the GWM
Reach with it. Or, as I said in my other post, each Feat should have a drawback to using it. So in stead of the -5/+10 as is, leave it in, but add
Attacking like this can cause you to lower your defenses, so any attacks against you that round from an opponent in melee with you gets Advantage. But just flat out numbers adjustments? Bad idea...really bad. It encourages min/maxing power-building as players try to give their character every bonus they can via any means they can just to offset that -5. If/when they succeed, it's basically a free +10 to damage. Terrible design if you ask me.
Of course, this trade-off does break down if you use 4d6-drop-lowest ability rolls. Characters with rolled ability scores almost always start with a prime stat over 16 before species bonuses, so they can max out that stat much sooner, making the trade-off between a feat and a secondary stat more attractive. (Hell, characters rolling for abilities with the 4d6 method can easily have 20 in an ability at level 1 once their species mods kick in.)
If you use 4d6-L? You do realize that is the default character stat creation method, right? Just checking.

And yes, that is how we do it...most of the time.
And what's wrong with character's adjusting their strategies once they learn a new skill?
It wasn't about adjusting strategies. It was a lot more than that. It was a character personality change. Like, up until level 4, the cleric was all about RP'ing that violence should be the last resort, or that a plan of attack should be agreed upon so as to minimize party casualties/damage, etc. But as soon as he got that magical -3 to damage taken...it was all
Damn the torpedoes! Full speed ahead! when fighting *anything* that was likely to only do small'ish damage (re: 1d4+1 or 2d4, or 1d6+2, etc). Yes, the tactics could have changed with him offering to go in first to draw attacks, or maybe positioning better so he could take on more than one at a time while protecting the wizard, etc. But it didn't pan out that way. It's like he was a new character.
And before you think of this as an isolated incident...no, it's not. As I said, I saw this phenomenon happen time and time again (usually not *quite* as extreme, but easily noticeable) with my group. Conferring with other DM's here in town and on the net showed me that I wasn't alone in seeing this. Feats are also an either/or thing, despite how the designers wanted it to be. If one player chooses Feats for his character, ALL characters need to start taking Feats or they risk being "one upped" by the guy with the Feats.
^_^
Paul L. Ming