Modern progressive systems not attached to blackjack sellers amount to moderations
of the traditional systems. They are moderated by mixing positive progressions with
negative progressions and/or moderated by early stops on the progressions. 

John Patrick's betting system provides an example of both moderations: 

2, 1, 2, 3, 3, 4, 5 stop or some variation like 2, 1, 2, 3, 3 stop. 

The stop moderates the duration. The progression could be extended to 4, 2, 4, 6 and
could win a lot more money but the liklihood of winning at each step is slightly less than half. Five wins in a row happen about once out of thirty-two starts and nine units are won. With a bet being made each minute the gambler will have two really good results an hour. But out of almost every other play he will not have a bad result. After a win, he will end up with a one unit win. Three wins in a row give a two unit win and this, also happens fairly often, one time out of eight. Four wins in a row wins six and this will  happen one time out of sixteen. The mathematically necessary losses of two units slightly more than half the time might be overlooked when it seems like you are winning well a fair amount of the time. 

The negative progressions after the first play insures a win for that progression; the negative progression aspects of not doubling after the third win but, instead, pulling a  unit insures now and again the progression will recover as much as a lost first bet. 

The Dahl progression in Progression Blackjack has gotten popular recently. This progression, 1, 1, 1.5, 1.5, 2, 2, 3, 3, 5, 5, 7, 7, 10 stop, is about like Patrick's. It has many small losses, many small wins, and now and again can win well. The two bets at each level and the fact bets do not double with wins allows some chip pulling with modest, locked in, wins but still leaves a home run capability. 

These are just two of an infinite number of progressions but they more or less define the nature of modern recommended progressions: conservative ones which pull some money as they progress. 

Blackjack and Gambling systems sellers normally sell similar conservative progressions as a part of their packages but these progressions need to be discussed in the context of progressive betting in blackjack. 

Progressive Betting in Blackjack. 

Successful progressive betting schemes require roughly similar amounts of wins and losses,  making blackjack particularly unsuited for progressions. About 10% of blackjack hands are pushed, the player wins about 42% and the dealer wins about 48%. The nearly 6% differential is made up by players' ability to split and double (along with the three to two blackjack payoff). A player wins less hands but wins about the same amount of money because he wins more money on about 10% of the hands that are doubles and splits. 

Some would say playing progressions should have no effect. The player splits and doubles when supposed to and things equal out. But things don't. The progression is not protected when larger bets have to be made to keep up the win rate. Two  examples: (1) Oscars Grind. Player down 25 units and betting 13 units. The player has the potential in two plays of finishing the progression. 8,8 v. 10. A split with a likely loss of 26 units ruins the progression. (2) Dahl's Progression. Won six hands in a row. The bet is three units. The player has a ten against the dealer's nine. Six wins in a row happen about once every hour and provide a fair percentage of an hour's wins. At this point in the progression, the player has won nine units, pulled seven units (one of which is his starting bet) and is betting three units of his winnings A loss of an undoubled bet will terminate the progression with a profit of six units. The loss of a double will make the winnings for the progression three units. And the play is close. Should the player make the mathematically sound bet of doubling or should he just hit? 

In a progression, protecting the progression is what is important. A progressive better would most likely hit and lose some of the advantage a normal player has. 

Since progressions depend on some uniformity of bet and some uniformity of wins and loses blackjack just does not fit progressive betting. 

And this brings us to the progressions of blackjack system sellers. 

Blackjack Systems and Progressions. 

Blackjack systems sellers (like most gambling systems sellers) primarily sell
progressions. There is normally a veneer of rationale justifying the progression because no progression in a negative expectation game can ever be justified mathematically. 

And persons selling blackjack systems have special problems justifying their systems
because there is a mathematically verifiable method of beating blackjack already
known and practically free coupled with the inherent strain the varied bets of blackjack
place on progressions. First, counting must be declared impotent and second,
progressive betting must be reconciled with blackjack. 

A neat tale is told to take care of these real problems blackjack system sellers have.
Proponents of card clumping say that card counting can only be justified if the
uncounted cards remaining in the shoe or deck demonstrate randomness. They say that if, instead, high cards are clumped with other high cards and low cards are clumped with other low cards, even if the counter knows the proportion of the cards left, it will not do the counter any good. Casinos, to thwart card counters and to make the game tougher to beat for basic strategy players, purposely "wash" (the initial mixing up when new cards are introduced) and shuffle to make and preserve clumps. Further, the nature of blackjack hands being put into the discard tray means clumping happens.Two high cards dealt to a player will remain together in a discard tray or if a lot of cards are drawn to a pat hand a small card clump will result. 

According to this theory, the shuffle means clumps will remain shoe after shoe and can
be exploited. Clumping characteristics which reoccur can be figured out. And if the
game characteristics can be so figured out, progressions can be devised to exploit these characteristics. Also, according to this theory, different strategy plays can be made. If, in a low clump, the player should hit 16 against 16. If in a high, he should stand on stiffs against dealer high cards. He can also predict the dealer's down card and hit, stand, double, or split based on the knowledge of the come card and the dealer's down card.

And the plot thickens. What strategy plays are changed by the system sellers'?
Invariably ones which lower a player's overall advantage by minimizing doubles and
splits. 

This congruence strongly suggests nothing is being sold except progressions. It also
reveals why the system sellers say what they say about clumping and counting.
Gambling using progression, gambling against probabilities, gambling giving up some of the advantage inherent in a game, has to be justified some way. 

But this is not a beat up on blackjack system sellers article except to the extent it helps
blackjack players understand progressive betting in relation to blackjack. 

A further step can be taken by an analysis of negative and positive progressions with a special focus on the limitations of the best known and most often rediscovered system,
   

  the Martingale.