Ok, time to make one more lengthy post on the subject, hopefully the last one so that I won't have to reiterate my view once again, as there seem to be some misconceptions about it that just
keep on appearing. :P
Also let me get this straight out of the way: I'm talking about credit-feeding, i. e. putting coins in mid-game as a means to get a free buff to the player character or circumvent a game over screen. I'm not talking about using deaths, as those are limited within each credit.
Using continues in arcade games, ports thereof, and console games designed in the same spirit, doesn't break the rules of a game the same way glitch abuse or simple death abuse does, because the developers have designed
two sets of rules. Credit-feeding circumvents the main set by forcing the player on a
pre-designed fallback routine that, in many cases, drastically changes the gameplay in ways that aren't particularly appreciable in TASes (again, assuming they are not about simply making an arbitrary number on a web page smaller at all costs). Arcade games
know it when you're doing this, and act accordingly, which is why it's very hard for me to consider feeding coins mid-game clever. You aren't fooling the game anyway, it just treats your actions differently. In essence, credit-feeding substitutes the concept of beating the game with the concept of just getting through it to the end credits. This means it changes the issue from a speed/entertainment tradeoff question to a goal question, or at least a categorization question.
Coins in arcade games are a vessel of income for the arcade operator, so naturally all arcade games are made hard and short. The reason is simple: faster credit rotation = faster money gain. Because of this you also can't pause mid-game, and all stages and bosses run on timers, preventing potentially infinite credits (unless the player is just crazy good to loop a game over and over). The challenge also needs to be there so that players who have beaten the game would play it again for fun. For this reason many arcade games employ dynamic difficulty system (commonly referred to as rank) that makes the game progressively harder if the player is doing well and, respectively, easier if he dies a lot, doesn't score, or doesn't power himself up too much. Classic example: Battle Garegga's last boss
played by a good player skilled enough to reach it, and the same boss
played by a WR holder. Note the difference. Obviously it can be thrown out of the window if the player suicides on a whim, having unlimited lives granted by continues.
Feeding coins mid-game has been allowed for the same reason as the high difficulty mentioned above: so that players who can't (yet) cope with it could still have some fun with the game (although exempt from the score ranking), see the content, and learn it — all the while bringing profit to the arcade operator. Because if this the use of continues is associated with free powerups, lowering the difficulty, granting additional lives (as well as an easier opportunity to get the score-based 1-ups in many cases) to bait the player into paying more. This completely defeats the purpose of setting the game on a higher difficulty, as you're just lowering it back this way.
Arcade games employ a scoring system that would make a small-scale or even large scale competition viable, because competing and making progress in more ways than just getting farther in the game is fun. No arcade game would let a player buy themselves a high score by putting in enough money. On the contrary, it would in pretty much all cases reset it or mark it as invalid with every subsequent coin, and in many cases completely exempt it from the scoreboard. The score must be
earned, separating the players who put beating the game as their goal from those who just want to see the end credits. Many games won't let you put in the first coin's score even if it beats an existing scoreboard entry as a means of punishment!
Many games have additional stages or so-called true last bosses that are only accessible if the player does not continue. Many games that have a second loop won't grant you the access if you so much as died once too many on the initial loop, let alone used a continue. Some won't show you a real ending, or even end credits at all, which brings me back to the point of what exactly should count as beating an arcade game.
Additionally, using free benefits throws such important and impressive aspect of TASing as resource management out of the window as coins, which are limited in the real world, are infinite in a virtual, so the need of planning is also thrown out of the window.
Because console games are designed around a different playing scenario, these differences need to be addressed.
1. You pay for the game only once. This is the reason there aren't as many (if at all) credit-feeding "tricks" available: you aren't bringing anybody profit by making the game easier. For the same reason, however, console games are also easier and usually don't have any dynamic difficulty curves, as dying frequently doesn't bring anybody profit anymore.
2. You aren't standing in a line when playing at home. Because of this you can pause, save, load, access later levels through various means. This is also the main reason console games are usually much longer: if there is no hurry, the developers can put more content, as well as more useless padding (I'm looking at you, Zelda) and backtracking (hello, Metroid). Games like these would never appear on an arcade cab because an arcade game is designed to be a whole and complete experience for 20–40 minutes, rarely any more. It is already an endurance test for most purposes.
This suggests that continues in console games are often (but not always!) a part of the system that lets you leave off and literally continue playing it at some later point in time. It doesn't have to be a way to circumvent a game over, although oftentimes it is required to make use of this system. Arguing the intentions of developers is a touchy subject ridden with prejudice and speculation, but in general, console games (unless they are, as mentioned previously, arcade ports or arcade-like games like the PS2-exclusive Gradius V) aren't designed to always be played in a single sitting, hence the well-understood need for means to access the later levels in some way. This means that getting a game over is sometimes a necessary step, and is thus normal for
some circumstances.
Upon inspecting this aspect further I've come to conclusion that with console games it needs to be decided on case-by-case basis. For arcade games, however, credit-feeding should just be prohibited. There are abundant reasons outlined in this post that justify this, so if you think it's unfair, well, I don't have anything else to say. There might be exceptions if abusing additional credits can reduce the length of the game drastically (like the aforementioned Bionic Commando example), but it still must be viewed as a deviation from the norm the same way NewGame+ runs, or runs that use codes/passwords for a direct benefit, are.
