Your first comment was this:
“Yeah, signing a 99 year lease, and actually having both sides honor the terms is a real trick. /S”
That lease is mentioned nowhere in the Joint Declaration and “honor[ing] the terms” of the NT lease had nothing to do with the Treaty.
ChiComs did use it as a pretext to threaten Hong Kong (as you spoke if positively) and extort the handover from the UK.
Oh for crying out loud....
The expiration of the 99 year lease (and the honoring of the terms by both sides) is the whole reason the talks took place! It says it right in the blasted Wikipedia article:
“The background of the Sino–British Joint Declaration was the pending expiration of the lease of the New Territories on 1 July 1997...”
Are you really this slow?
“ChiComs did use it as a pretext to threaten Hong Kong (as you spoke if positively)”
Once more in English....and maybe with fewer bong hits?