Yes, exactly the same thing. In each case, the fact that some of the weight of the compound is constituted by the counterions doesn't mean that the substance is impure. Conceptually, it is possible for any compound to be 100% pure. The levels or purity stated in Breaking Bad, fwiw, are not only possible, they aren't even that impressive for a man who is supposedly the greatest amphetamine chemist of all time, the DEA regularly sieze crystal meth that is 99% pure. People often talk about it being impossible for MDMA HCl to have greater purity than 84%, this is, again, a misconception.
You should just be able to let water or solvents evaporate. Base sometimes does have a strange, heavy, greasy component that doesn't evaporate, I don't know what it is, and there's not much point in my speculating.
I don't agree about the DEA regularly seizing 100% pure d-methamphetamine. Below I have two paragraphs, first one from US media showing the American perspective and the second from an Australian media showing an Aussie perspective...
1. "During that same period, the purity of Mexican meth shot up too, from 39 percent in 2007 to 88 percent by 2011,
according to DEA documents. The price fell 69 percent, tumbling from $290 per pure gram to less than $90."
http://www.usatoday.com/story/news/nation/2012/10/11/mexico-cartels-meth/1626383/
2. "Arrests for clandestine drug laboratories are at record levels.
The number and weight of seizures internally are up more than 50 per cent on last year.
Purity of the drug in some regions is as high as 80 per cent."
http://www.news.com.au/national/dea...-the-new-ice-age/story-fncynjr2-1226758663681
The first paragraph states that purity levels for large seizures of Mexican d-methamphetamine in the USA(by DEA) at around 88%, now take into consideration that other than Chinese and other major Asian manufacturers, the Mexican cartels and their super labs would be one of the best funded and equipped in the world, and they can not pump out 100% regularly. Low 90s would be the maximum and batches of that purity would be rare.
The second media paragraph states how Australian labs are producing high purity d-meth at around 80%, (take into consideration that Australian cooks have been honing their skills for many years and the fact australia is very close to Asia with their high purity precursors)
By looking at stats from two different places in the world with long and high reported d-meth usage, it seems high purity d-methamphetamine ranges from 80-88% there.
Of course that figure does not include purity amounts from the king-pin methamphetamine producing nation which is china, so I'll go at a whim and say including china the purity range would be 80-90%.