'Reflowing' a joint is a surprisingly popular way to make a bad joint which may look good on the surface.
During my 50+ years of homebrewing and kit building, I've used the mount, solder and clip procedure and then had a brief go at "reflow" soldering to make the joint look better.
You can install several or more resistors at once, using the long leads to hold them in place by simply reaching under the board and separating the leads away from the resistor body with your fingers to hold them in place, then flip the board and solder them all at one time. Not the way most step-by-step kit directions read, but great methodology for the experienced board populator and faster.
This is the procedure I've always used and can add only one thing. Before cutting the leads I make sure the component is flat against the PCB (resistors, diodes, elect. caps, etc. - Disc caps vertical with the same leads length in each hole)
My findings are that the "reflow" joint can hide a poor solder connection as HQP points out. I've actually had bad solder connections hidden by a beautiful, shiny spot of solder! They ususally look so good that it's easy to tell yourself, "That's a beautiful joint so the problem can't be there."
I also found that "reflowing" a joint for solid state devices increases the chance of ruining that device by overheating. Reflowed joints have more solder which holds the heat longer.
I have never had a solder joint ruined by "shock" from cutting the lead. By the time I put down the iron and pick up the wire cutter and move to the lead to be cut, the joint has solidified sufficiently to withstand any shock.
The only exception to this that I can think of would be terminal strip joints which contains more than one lead.