Reading through the various posts on the decline of martial arts (something which I will have to weigh in on someday), I was thinking a good bit about the Beggar Clan. It is something of a microcosm of the entire Jianghu due to the diversity of its members and its prominence in Jin Yong's various works. In particular, the degradation of the Beggar Clan's treasures, Xianglong and Dagou, is interesting. For reasons that are fairly obvious, I shall focus on the novels from TLBB to YTTLJ.
Starting with the creation of the Beggar Clan in the Tang dynasty, both treasures (probably created by the clan founder) have been passed down straight to YTTLJ. It should be noted that the third leader of the Beggar Sect was mentioned to have perfected Dagou. In TLBB 3e, XiaoFeng and XuZhuZi streamlines Xianglong into the form that is most familiar with readers. I would argue that Xianglong reached its peak in the palms of GuoJing, who incorporated his understanding of Jiuying into the techniques, but XiaoFeng is a formidable contender to that title.
It is interesting to look at the old versions of Jin Yong's novels for comparison. In the Ming Pao edition of SDYXZ (1e), Hong QiGong's Xianglong was half taught by Leader Qian, half self-created. Even when Guo Jing learnt the initial 15 palms, he was able to create 3 ersatz palm techniques on his own to fill in the gaps until Hong taught him the real (and far more powerful) techniques. In other words, the 1e Xianglong had undergone reconstructive surgery from TLBB to SDXYZ. In 2e, Xianglong was passed down as is. In 3e, Xianglong underwent liposuction, going from 28 palms to 18.
The depiction of Xianglong from SDXL to YTTLJ in 1e is another interesting change. In 1e, Xie Xun knew several palms of Xianglong, but lacked the knowledge to realise their full power. He taught these to Zhang Wujie, who used them right up until he learnt QianKun. Zhu and Wu also knew bits and pieces of Xianglong, but were also unable to realise their power. In the Beggar Clan, there was of course Shi Huolong who knew 12 palms, but also Chuangong Zhanglao, who used it against Hebiweng to great effect. Finally, there is Guo Jing's Xianglong shortcuts in Yitian. All these were cut out in following editions.
To me, the loss of Xianglong seems to be incomprehensible. Jin Yong's depiction of it seems to tend towards easy to learn but hard to master. Guo Jing could master Xianglong in several months, so why should it be lost (partially anyway) after him (or YeluQi in YTTLJ 3e)? There is no particular reason why Clan leaders could not learn it due to lack of intelligence - Guo Jing is the brawn, not the brains of the Guo couple. Even if according to lack of talent, I find it hard to believe that Dagou can be passed down in its entirety to Shi Huolong but not even the remnants of Xianglong - especially when Xianglong is the technique that is not limited to the Clan leader! Particularly in 1e, the amount of people who know some Xianglong is outrageous - given that Hong Qigong was able to create 9 palms to complete the set, I should think someone would be able to come up with something to replace what was lost. No wonder Jin Yong made Xianglong a Macguffin in later editions. It still begs the question of why Dagou wasn't lost at the same time though - look at Lu Youjiao. Granted, it is never mentioned if he learnt Xianglong at all (!!), but given his difficulty in learning Dagou, would someone of lesser ability be able to learn it any more than Xianglong?
As a side topic, there were originally 2 "Crown Jewels" of the Clan. One is the Dagou Bang, of course. But the other is Hong Qigong's wine gourd - the one which was buried with him. This gourd was ruby red and abnormally large (it was slung across the back) and played a role in SDXL - Pang Zhanglao and one of his cronies used a fake to relay false news regarding Hong Qigong in the Convention. The gourd is probably a reference to JiGong, and was taken out because its depiction was nonexistent in TLBB (Not to mention the idea of generations of spit accumulated in that gourd... urgh).
The decline of the Beggar Clan has much to do with its internal politics as well. Apart from the Clean and Dirty Parties, the power balance between the various elders and the Leader has a large role to play in its decline. Hong Qigong and Huang Rong are leaders in absentia, leaving Lu Youjiao to do most of the day-to-day management, while Shi Huolong was gone for 20 years by the time the major events of YTTLJ occurred.
Personally, I think the peak of the Beggar Clan's might was reached during SDXL - It is certainly when the seeds of the Clan's decline were sowed. From Huang Rong through Yelu Qi, the Beggar Clan was controlled by the Guo family. Even during Lu Youjiao's reign as leader, I suspect Huang Rong was leader in all but name - As noted before, it is not mentioned if Lu Youjiao ever learnt Xianglong at all, for one thing. For another, Lu Youjiao was already running the day-to-day business of the Clan when she was in recluse at Taohua Dao, and later involved with Xiangyang - there was no real reason that she had to hand over the reins. In reality, nothing changed - she was still the Queen of Beggars. This is even more true once Yelu Qi assumed leadership. In YTTLJ 1e, this goes even further - Yelu YuanRu was mentioned in passing as the leader of the Beggar Clan in Zhang Wujie's youth. It would seem that certain heredities have emerged in the Beggar Clan, which would add to the decline. Certainly, the selection of Shi Hongshi as a puppet leader and the loss of the 4 elders meant a gutting of the top echelons and assured the final decline of the clan.
I wish I had more to say about Dagou, but there isn't really anything. It was passed down straight to Shi Huolong and lost - the stick essentially being a sceptre of power afterwards.
I should read up more on the politics of the Beggar Clan as well - there are bits and pieces of information scattered throughout the corpus which paint a fairly complex picture. Simply going through the various positions and titles of the Clan throughout its history is a formidable challenge.
Comments and corrections are most welcome, of course.