I think this depends on how you implement it. I've been a part of several startups that have issued shares to founders on Day 1, and
every single time issues have arisen down the road.
* The partners were equal at the beginning, but down the road, their value and contributions weren't equal
* Passive partners were given the same share as active partners
* People were brought on out of loyalty, not because of their value going forward
All three of these problems can lead to instability and conflict.
Partnering is serious business, and it's important to do it right. If people are bringing money to the table, it's relatively simple - value the company and issue shares. But when a company has no value, or if you aren't even sure where the company will go, it's important to vest ownership progressively, based on contribution. Not to say that this is easy, but it's better than just issuing everyone 1,000,000 shares at the concept/seed stage.