The secret to mk multiplayer has always been to be in the 2nd-4th standing for the majority of the race, because the handicap is so much better there than in first.
In first you really don't get any good drops, but you can still be very close to the the person in first place while still being third or fourth.
If you take the early lead and try to hold it, chances are, you aren't actually a smart racer.
The strategy in MK is to place yourself so that you can pick up the drops you need, position yourself, and secure the victory. This stategy in most games is called a "gambit", though this would be a variation. Take a disadvantage in order to gain strategic positioning.
There have been times where I've held a mushroom for multiple laps simply for exploit purposes, when I thought the chances were low I would get another one.
