Re: #1 and #2
Yes, but then they could be deceiving themselves in terms of thinking that they are more competitive for admission than they actually are, particularly if their high school has very heavy or exaggerated weighting. For example, a student may think that their 4.2 weighted GPA makes a college listing a 3.8 average GPA a “safety”, not realizing that their 4.2 weighted GPA came from a 3.4 unweighted GPA that makes that college a reach.
Unfortunately, it also seems that the deception often “works” on posters responding to threads in the “college search & selection” and “what are my chances?” sections, since most of those replying take weighted GPA at face value without any information on how it was weighted.
Conversion of 100 point transcript grades to 4 point grades is a whole other topic where there seems to be no universal standard.