I have never operated a crane but have spent a lot of time on digger derrick trucks. The type used by utilities for line work. Operation of these are basically the same but on a smaller load scale. There are load charts (or should be) for the operators reference. With a crane, the reference chart includes what you can lift depending on the counter weights you have on the rig. Wind speed also comes into play with cranes. The footing of the outriggers should really be a no-brainer for an experienced operator. The common denominator in the recent videos posted here is that the boom of the crane was lowered to a very low angle to reach out across to the point of placement of the load. This greatly decreases the amount of weight the crane can lift safely. As an example: Pick up a fifty pound weight with one hand, then try to pick up the same weight with your arm fully extended. Where this crane might have been able to pick a 5 ton load with the boom at a high angle, it might only be able to pick a load of a few hundred pounds at a low angle. I the end it is the operators responsibility to know the charts at the configuration of his machine. Sometimes the lowest bidder isn't the best choice.