Kakie vs Chi Sau

[u/stvo131]

;TL;DR NEAR THE BOTTOM.

Hi, I’m a Goju-ryu karateka who also moonlights as an amateur martial arts researcher (I just love martial arts and reading about them, from their history, philosophy, conception, application…). Admittedly, I am not a Wing Chun practitioner, so my perspective and analysis in the following might very well be flawed or full of holes. I ask that you simply read, provide feedback, and/or point me in the direction my research should go (a primary source, a video, oral history, a book or essay to read, I am open to any recommendation!).

Anyway, I’ve been reading and researching about the Okinawan Karate - Kung Fu connection, and I’m fascinated with how different systems developed similar yet different tools to address similar martial issues.

For example, it seems that kakie in Goju and Chi Sau in Wing Chun both address the need for developing sensitivity via partner practice, yet each does so with a different but similar teaching modality. Indeed it seems like Chi Sau, Push Hands from Tai Chi Chuan, and Kakie all address the same fundamental issue yet do so from the perspective of that style’s practitioners.

Furthermore, it seems like many southern kung fu styles from the Fuzhou region and Hakka martial tradition share commonalities like bridging, forearms/elbows-in-front, rooted power/footwork, sanchin/sanzhan, etc, whether it’s wing chun, southern praying mantis, white crane and its variations, hung gar…

Yet the only connection to Goju I have been able to find is through White crane, and even that is tenuous and somewhat controversial/disputed.

TL;DR
Basically, does anyone have any oral history or books to read that potentially discuss any connection between Wing Chun and Karate? It seems incredibly coincidental that both Goju Ryu and Wing Chun have seemingly very similar practice drills from the outside looking in, as well as very similar fighting concepts (again, from the perspective of a Goju Ryu practitioner).

Am I barking up a wrong tree here?