Well it is possible it could happen, but not likley
A good condition clutch properly adjusted should be fine.

He may have been referring to some of the older metrics.
I noticed on mine (Kaw and Hon) that they would slip if I had
Synthetic in it or an additive like prolong.
Wasn't much of a slip but it was there.

 

actually very little oil gets to the discs. the oil circulates over the clutch housing for cooling. i have used type F ATF for over 60K miles, the friction modifiers help the clutch discs grip just like using type F in GM transmissions for shifting.

 

I guess you believe what you want to believe or from personal experience:

From an amsoil dealers website:
Q: What is the purpose of the oil in a 'WET' clutch?

A: The primary purpose of the oil in a wet clutch is to act as a coolant. The oil flows around the clutch plates and friction plates, cooling them. This results in smoother clutch action and prolongs clutch life. Be sure to use a motorcycle specific oil, such as AMSOIL Motorcycle Oils, which has absolutely no friction modifiers and is fully compatible with all wet clutches and meets/exceeds all JASO motorcycle wet clutch specs. Do not use automotive type oils in a wet clutch because they have friction modifiers, which depending on the specific oil and friction modifiers, can cause clutch plates to slip and run hotter which allows for glazing and heat related issues to occur.

From nightrider.com:

Q: What about using Synthetic Oils in my clutch?
A: Synthetic oils, by their very nature of better heat resistance and improved lubricating properties, would seem to have an advantage. This is an advantage when it comes to lubricating an engine or transmission, but turns into a disadvantage when used in a clutch. This increase in lubricating properties (they are slippery) can cause an old, worn out clutch to fail. The purpose of the oil in a wet clutch is to cool, not to lubricate. The more 'slippery' an oil is, the more likely a clutch is to slip, resulting in increased heat and creating excessive wear.
While most high performance clutches are designed to work with synthetic oils, it is not recommended that they be used by most clutch manufacturers. Synthetic blends are usually considered acceptable

 

Amsoil MCF is recommended for the engine, tranny, and primary. I change them all every 6000 miles. 40,000 miles and no problems. This guy is a idiot he should read about the products he wants to sale.

 

I too switched to ATF in the primary a couple years ago. Had run expensive synthetics in there the first few years, but once you understand the purpose of the lubricant in the primary, you realize what a terrible waste of money it is to throw synthetic oil in to lube a chain and clean/cool clutch plates....PLUS YOU KNOW THERE IS NO HARMFUL FRICTION MODIFIERS IN THE ATF.