FAT file-system between the MBR and first partition

I have an old 64MB USB flash-disk which seems to have MBR:

root@3:~# fdisk -lu /dev/sdd

Disk /dev/sdd: 64 MB, 64880640 bytes
2 heads, 54 sectors/track, 1173 cylinders, total 126720 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x6f20736b

   Device Boot      Start         End      Blocks   Id  System
/dev/sdd1            2048      126719       62336    6  FAT16
root@3:~# 

/dev/sdd1 is a FAT16 file system:

root@3:~# file -s /dev/sdd1
/dev/sdd1: sticky x86 boot sector, mkdosfs boot message display, code offset 0x3c, OEM-ID " mkdosfs", sectors/cluster 2, root entries 512, Media descriptor 0xf8, sectors/FAT 244, sectors 124672 (volumes > 32 MB) , serial number 0x6b067135, label: "           ", FAT (16 bit)
root@3:~# 

I'm able to mount this /dev/sdd1 partition and read and writes file to it. Now the weird part is, that I'm also able to mount /dev/sdd and I am able to list the files on that file-system. File-sytem on /dev/sdd seems to be created by Windows XP as it used MSDOS5.0 as OEM ID:

root@3:~# file -s /dev/sdd
/dev/sdd: sticky x86 boot sector, code offset 0x3c, OEM-ID "MSDOS5.0", sectors/cluster 2, root entries 512, Media descriptor 0xf8, sectors/FAT 247, heads 255, sectors 126720 (volumes > 32 MB) , serial number 0x50435598, unlabeled, FAT (16 bit)
root@3:~# 

In addition, once I mount the /dev/sdd to /media and execute ls -l /media, one of the files is named "New Text Document.txt". I know that it is possible to create a file-system directly to device without partitions, but in that case there will be no MBR and fdisk should complain that there is no valid partition table.

Am I correct that probably there was a FAT16 file-system created to the whole USB flash-disk under Windows and then later there was a MBR and single partition created to this flash-disk, but area from sector 1 to 2047 was never touched and there was Windows created FAT16 file-system structure in place at least to extent that I was able to mount this with mount utility?