Legalising ball tampering: Saliva is must and vaseline is no replacement, feel Nehra, Harbhajan

Saliva and sweat are components that cannot be entirely done away with, insist a few distinguished India cricketers, as the ICC contemplates legalising ball tampering post COVID-19 by using artificial substances to prevent virus spread.

Former India pacer Ashish Nehra and spinner Harbhajan Singh feel that saliva's use in shining the ball is a "must". Ex-opener Aakash Chopra, while beng open to the idea, wants to know where one can draw the line.

While discussions are at nascent stage, questions are already being asked about what external substances could be used if ball tampering becomes legal?
Is it going to be bottle cap in pocket to scuff up one side of the ball, vaseline to shine (made famous by John Lever) or chain zipper?
"It's not that murray mint can be used without putting it in your mouth. The coat of sugar on the saliva makes it heavier after one side gets scuffed. A scuffed up ball is also good for spinners as it ensures a better grip than a shiny new ball. But my question is, if you allow, what's the limit?