why should burn stop exactly at 34%

[Chewy]

was the disk branded Imation?

[paglamon]

No.On the box it is written Moserbaer Pro.
Here is media information and complete media code from DVD Identifier.

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Unique Disc Identifier : [DVD+RW:MBIPG101-W04-000]
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Disc & Book Type : [DVD+RW] - [DVD+RW]
Manufacturer Name : [Moser Baer India Ltd.]
Manufacturer ID : [MBIPG101]
Media Type ID : [W04]
Product Revision : [Not Specified]
Blank Disc Capacity : [2,295,104 Sectors = 4.70 GB (4.38 GiB)]
Recording Speeds : [1x-2.4x , 1.6x-4x]
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[ DVD Identifier - http://DVD.Identifier.CDfreaks.com ]
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** INFO : Hex Dump Of 'Media Code'-Block Listed Below
** INFO : 4-Byte Header Preceding 'Media Code'-Block Discarded
** INFO : Format 11h (Method 1) - ADIP Information
0000 : 92 0f 04 00 00 03 00 00 00 26 05 3f 00 00 00 00 .........&.?....
0010 : 00 00 01 4d 42 49 50 47 31 30 31 57 30 34 00 39 ...MBIPG101W04.9
0020 : 23 00 94 79 64 02 20 00 9c 7a 6c 02 20 00 9a 7b #..yd. ..zl. ..{
0030 : 68 02 20 12 12 10 e0 00 f0 00 00 00 00 00 00 00 h. .............
0040 : 01 00 17 38 00 29 8b 3e 02 24 00 2d 8e 38 02 24 ...8.).>.$.-.8.$
0050 : 00 2c 90 3e 02 24 44 35 30 e0 f0 30 40 00 00 00 .,.>.$D50..0@...
0060 : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
0070 : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
0080 : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
0090 : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00a0 : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00b0 : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00c0 : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00d0 : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00e0 : 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00f0 : 00 00 00 00 00 00 00 00 ........