Nope. You don't want to heat it to where it boils--that'd be hazardous to your health!--but hotter is better, in the general case. I'm no SME on the subject, but, its like you want the copper pad to heat up really fast, solder really fast, then you're done. We don't think of FR4 as being a conductor of heat, but it does pull heat, it's not a perfect insulator.
Thought of differently: let's say your iron was 317F. You touch solder to it and it melts. Now you put the iron to the copper pad and touch the solder to it. What happens? nothing happens, because as soon as it touches, heat leaves the tip and now it's 315 or probably less, much less. As soon as the tip hits that copper pad, it starts losing heat. As soon as you touch solder to it, it's losing heat. As soon as the flux melts and starts flowing, it's "flowing" heat away from the iron.
How fast does the tip cool, and how much does it matter, eh, couldn't tell you, I've never tried to solder at low temperatures. I'm not an expert on PCB's but I will tell you, soldering temperatures, at any, degrades the plastic material that the laminate is. The longer you have it hot, the more damage occurs. Not only that but as you solder, the protective layer of metal above the copper trace is slowly absorbed into the solder joint itself. Once it disappears, the copper itself becomes next in line to be attacked--and it's going to degrade quicker than what was above it (often it's nickel). But this is happening at the same time that the FR4 is gassing out. And at the same time, you're well past the point where the FR4 is considered "solid", it's now above what's considered the glass temperature, where it's now "soft". Before long, the PCB pad will lift off the board, and it's game over.
Link to an article about Tg.
Another link about soldering temperature discussion.
Note, reflow soldering (where you apply solder paste to the pads, then place the SMT parts, then bake the assembly so that the solder paste melts) is done at lower temperatures, but as a process, it's different: the entire assembly is heated all at once, and even then, it's a quick ramp up, with a limited time at solder paste melting temperatures. Again, you're well past the temperature that the laminate is rated to live at, and it's outgassing at even these lower temperatures of 500F or so, so dwell time needs to be limited.