Any player capable of get a fw update can read any type of DVD bitsetting, but due to a DVD war stated by some manufacturers (as Panasonic and Toshiba) their players doesn't have specified the bitset for DVD5/9 +R/RW. Only most of players have specified to recognize the media as follows:
DVD-R (0010) for DVD5 and DVD9 both
And are not programmed for
DVD+R (1010) (due to the format war or very old player)
DVD+RW (1001) (due to the format war or very old player)
DVD+R DL (1110) (due to the format war or very old player)
DVD+RW DL (1101) (due to the format war or very old player)
DVD-RAM (0001) (due to hardware limitations)
The player can fisically read all possible bitset, but it is not programmed to play all posible bitsets. If it can read the bitset zone, so is hardware capable of play the disc, but software RESTRICTED to play it.
Due to the "format war" Philips and HP created a DVD+R/W emulated as a DVD-ROM, so the player can identify it as a valid DVD-Forum format, and eliminated the pre-recorded bitsetting, allowing to the recorder write the bitset. This trick worked because the player recognize it as a DVD-ROM specs stated in the DVD forum.
That's why OC-Freak stated that bitset in DVD-R specs is not possible. (by now, but if the -R recorder is designed as a +R specs to write the bitset and eliminate the pre-recorded bitset in the media , so it will be possible)
Only players that can't read DVD-RW media can't read DVD+RW media.
If the player was programmed for that, so it can read it.
Theoretically any DVD player is capable of read ANY dvd type (DVD-ROM, DVD+-R/RW DL/SL, except DVD-RAM) if it has programmed the specification needed in the firmware.
The player reads or not the DVD recorded only if it has the quality needed to read it and if it was programmed to read the booktype.
Any player with a flashable firmware can read all types of DVD created (except DVD RAM) if their manufacturer program it. It's a firmware programming matter, not MEDIA matter...
Another problem is that if the player is programmed for DVD-R as 4.7 Gb as max capacity and found a larger capacity disc it will not play due to the firmware, but it is hardware capable. But the fw need to be modified...
That's why code65536 stated the DVD-R Part Versions (1.x for 3.95 GB, 2.x for 4.7 GB, and 3.x for 8.5 GB)
Burning media is another history... Totally different...
Same will happen with new format war BD and HD-DVD, a totally new incompatible formats
(sure the worst english you ever read) :o