I've imported a .csv file (with relative .csvt) in QGIS 2.8.4 adding a delimited text layer... the table was correctly been imported but the table fields have a length of zero... the fields types instead have been correctly read from the .csvt, which obviously specifies also the fields lengths.
According to gdal.org/drv_csv, you can define width and precision in the csvt file.
According to Why are some columns not recognized as numeric even though I have a CSVT?, QGIS does NOT read the csvt with
Add delimited text. Instead, it makes some kind of educated guess about the data types
Add Vector Layer instead. Draging and dropping the csv file from an explorer window to the legend will do the same, as you experienced.