Is it a good idea to keep MacBook Air in all the time

Question

I basicly used it on my desk all the time. I leave it in sleepmode too while plug in is it okay to do this

Answer 1

That you have "experience" is not in doubt,…. if however you think you or myself cant LEARN anything , then its an untenable position to take on ANY subject.  I repaired laptops for 10 years, I have experience too, like yourself, likely more than yourself in said area.
I refer you to   maxamps.com,    battery university,    …. and Dr. Rudolph PhD in Mechanical Engineering, Technology Manager for Lithium-Ion Battery Factories: >
*Perhaps one of the worst locations for a Li-ion battery is in a laptop computer when used daily on a desktop with the charger connected much of the time
*Permanent Li-Po battery capacity loss is GREATEST at elevated temperatures where the battery voltage is maintained constantly at peak.
*There are two types of battery capacity losses: recoverable loss and permanent loss.  Recoverable loss (drainage due to use) can be recovered by recharging the battery. Permanent capacitance loss is NOT recoverable mostly due to charging and discharging INCLUDING minor capacitance drop and gain (partial charging; also deemed bump charging).
*Always maintaining a Li-ion battery in a fully charged condition WILL SHORTEN its lifetime. Chemical changes occur in the Lithium Polymer pack-cell and lifetime diminishment begins and are accelerated by high float voltage and  CELL DELAMINATION