Yes "we" because there are simply too many feats out there to keep the discussion rational.
How many combat feats are there in the PHB & Complete Series alone? There's probably at least 30 that would affect the discussion, and if you want to discuss what happens when you throw those into the mix, you're biting off a huge chunk.
Prioritizing Dex instead of Str initially usually indicates a design choice that will lead to different item choices though.
True- the Dex monk will gravitate towards items and feats that reinforce his forte, with Str boosters being secondary, and vice versa.
If you decide to pick Dex over STR, the same reasons will apply when it's time to buy to your first stat booster, or a few AC items vs Mighty Fist. Item choices usually aren't mad in a vacuum.
I didn't say they were- what I'm asserting is that if you posit a hypothetical in which the Str Monk has a BoGS, unless you make a lot of assumptions about the build of the Dex Monk (like the aforementioned Feat choices), his best option to keep pace with the Str Monk in the hypo is probably to take the same BoGS.
Man, if you frequently get to use all the AoOs from Combat Reflexes... Even using reach weapons, I almost never see characters needing more than a handful of AoOs. With 5ft steps, tumble, reach, special movement, etc AoOs don't come up that often. And when they do, the threat of having many extra AoOs is almost as good as the actuality.
Well, my last monk was very atypical, and had access to Feats from the
DCv1: Githzerai with a 26 Dex, 19 Wis, and a Bisento (reach polearm 1d12 x3). Stationed near the center, he was able to accentuate the attacks of the party's Barbarian quite well, and 8 AoO's + Bisento Flurry of Blows = nobody flanked him to get to the spellcasters.
Did the CRef have diminishing returns? Sure...but the overall point of the Feat is to help control the battlespace. If you control the battlespace, you win the battle. If the foes stop trying to flank the Monk to get to the spellcasters, they can lob as they will, unmolested.