Hi Peedee
I would say the private investor is like a Cheetah. Fast agile and moves in and out without a problem.
When you say professional I presume you mean corporate. In which case they are like Elephants, big slow and can't move around a lot.
Private investors have the upper hand as they have a lot less regulation and they can sell a whole stake in one go, where as corporation have to sell bit by bit.
HTH