No problem at all. You can leave your Mac connected to the charger as long as you want.
Be careful with that. There is no safety risk, but leaving it plugged in all the time will shorten the battery's life.
From the link you posted:
For proper maintenance of a lithium-based battery, it’s important to keep the electrons in it moving occasionally. Apple does not recommend leaving your portable plugged in all the time.
Rapha, One thing to be aware of. Li-Ion batteries, as all batteries do, have a finite number of charges before they die. I suggest you keep your MacBook Pro plugged in most of the time and then once every month or two let it run down and do a full charge. I have had my MacBook Pro for over a year and only disconnect it every two months and have had no problems with the battery.
This is from the same paragraph from the link posted. Always read the full article don't just pick one thing to hang on too.
If on the other hand, you use a desktop computer at work, and save a notebook for infrequent travel, Apple recommends charging and discharging its battery at least once per month.