Also I think you are still misunderstanding 5/24. It is only affected by your credit report. For instance I was at 3/24 at the end of October. I applied for both the Amex Platinum and the Hilton card on the same day. Amex doesn't report until your second billing cycle. A few days later I decided to go ahead and apply for the IHG card. According to my CR I was only at 3/24 because the Amex cards hadn't reported yet. I was at 3/24 for almost a month before the IHG card hit my report, making me 4/24. My Amex Platinum will post sometime tomorrow night or the next day putting me at 5/24. But until then, Chase will only see me as being 4/24.

Yeah, I understand that about non-Chase cards for sure, but Chase (if they want to) could see that someone has new cards with them (although not on the credit report yet). Maybe they'd never do that though...? Cheers,
--Kyle

Actually, that's not quite correct. It's not the card issuers who combine pulls. It's the bureaus (EQ/EX/TU) who combine pulls if they can't tell them apart. The pull only includes information about the issuer and the date, and so if two pulls come in looking the same with the same date, the bureau can't be sure whether they're duplicates or not, so they don't count these potential duplicates.

The reason business and personal pulls don't combine at most banks is because the bureau can tell them apart, because the issuer puts info in there that's different for personal apps than for business apps, because they're handled by a different group of offices within the bank. So a bank A personal pull might come into the bureau saying something like "bank A consumer services" while a bank A business pull might come into bureau saying something like "bank A business services". The bureau can't tell two "bank A consumer services" pulls apart from each other that have the same date, but it certainly can tell there difference between "personal" and "business". (The actual IDs of two groups within the bank may be very different -- they could be alphanumeric mumbo jumbo, for all I know -- but the illustration is just to make clear that they are different enough to not have any risk of being duplicates of each other.)

We have plenty of data points (in the Applying thread) that show that for whatever unknown reason, Chase evaluates 5/24 by looking at your credit report and nothing else (specifically, nothing within Chase's databases). There were people who applied in cases where they'd be at 6/24 or above if Chase was counting their own business cards opened months ago, but 4/24 or below if Chase's didn't count those, and all of those people were approved. Multiple data points of that sort proved that Chase wasn't counting their own business cards.

Now, of course, Chase could change how they do this count tomorrow. But so far we have not had any datapoints showing that they've changed their count.

Ie, we're not guessing about what Chase does. We're gathering evidence about what Chase does. One person can't do that easily alone, but a collective community like FlyerTalk can.