Understanding swing is not a matter of opinion. It's clearly defined in the curriculum of the Associated Boards of the Royal School of Music (ABRSM). The problem is they don't call it swing. They define two types of rhythm. Simple Time, which we can call straight rhythm, and Compound Time which gets called swing. Unfortunately not all Compound Time is called swing. Jigs and slip jigs are Compound Time (each beat divides into three). Swung hornpipes are also Compound Time, straight hornpipes are not. Four beats in Compound Time should be written in 12/8 time. This is more difficult to both write and read than 4/4 time, so the use of 'forced' triplets in 4/4 is an attempt to simplify (which of course leads to more confusion to people who are not comfortable with notation).

The dotted eighth followed by a sixteenth is another attempt at writing swing in 4/4 time. To me it sounds different to 12/8 but maybe to others it doesn't.

Other ways of indicating swing in 4/4 time include two linked 1/8th notes, an equals sign followed by a triplet in 8th notes above the score or something like the word 'lively' in the same place.

Pretty much all the responses posted here are saying the same thing. Most early jazz music was played with swing. If you can get the rhythmic feel in that music you will get what you want. Notation is notoriously inadequate when it comes across subtlety in music rhythms. Hence the importance of feeling and ears. Start feeling your ears folks.