If I encounter the 1,"This... that you showed, I expect my array will just have 3 elements instead of the normal 10

1,"This, or this and that",3 will result in 4 (not 3) entries if you use a simple split. The important point is that split will not distinguish between the comma in the quoted string and a comma used to separate fields.

If your data contains no strings then you won't have a problem. If it does contain strings you may encounter some rather subtle bugs including silently producing incorrect answers.