As you can see, I resisted simplifying this crossover in order to reach perfection regardless of cost. The woofer filter consists of a single inductor with 2 response shaping LCR notches, one series and one parallel. The tweeter filter consists of a single padding resistor (R0), 3 core response shaping components (C1, L2 and R3), a ladder delay network (L4, C6, C7 and L8) and an impedance flattening conjugate notch (C10, L11 and R12). R0 is used instead of a L-pad located after the filter, which has some tweaking benefits to be shown later. The XT25 is a tweeter without ferrofluid and it has a huge, sharp impedance peak. The conjugate notch is required. Without it, the tweeter will ring at the Fs, causing audible distortion. It's a little more obvious with an LR2 system. The XT25 is one of the most misused tweeters around because many choose to use it without a notch, and the shunt resistor in an L-pad often isn't enough to damp the peak. There's nothing too out of the ordinary about the crossover, except the appearance of the ladder delay network which doesn't seem to be used in other designs very often.
The ladder delay network is really the secret to this crossover. There are 3 passive solutions to the problem of mismatched acoustic center offsets common to LR2 designs. The first and most common is asymmetrical crossover slopes and the other common solution is using a slanted baffle. These work but are not optimal. Asymmetrical crossover slopes cause poor phase tracking around the crossover point which can remove a level of coherency depending on how severe the phase angles don't line up. (this is debatable and unproven however) There's no problem with crossovers that are mildly asymmetrical, but if you have to go more than one order in either direction on either slope, there can be some problems with the drivers not summing to flat. Slanted baffles represent a couple a different problems. First off, the drivers are off axis, which affects vertical off axis response and rolls off the top end response of both drivers. With the XT25, that's a big issue. Sure, using a 3/4" dome would solve the top end off axis issue, but I have not seen any acceptable 3/4" domes. The Hiquphon doesn't even come close to the performance required in a reference level design like this. Other 3/4" domes don't have the low end balls to pull off a LR2 crossover.
So, with all that in mind, you can see that the ladder delay network is the best solution in this system. It allows us to use a flat baffle, getting us the most out of the XT25's top end and giving us good phase tracking around the crossover point and symmetrical lobing when hitting LR2 targets perfectly.