I think Felix's question is deeper than the two previous answers would indicate. First of all, the question of whether Gothic Chess "takes longer" should be interpreted as "takes longer on average". Ed has stated on his website http://www.geocities.com/bow_of_odysseus/why_change.html that the average length of a game of regular chess is 55 moves and that the average length of a game of Gothic Chess is 30 moves. If we agree that "length" means "number of moves required to decide a game", this would indicate that Gothic Chess is significantly "faster" ("shorter") than regular chess. However, this difference in the length of Gothic Chess games versus regular chess games appears to be a result of the "increased firepower" on the board (Chancellors and Archbishops) rather than from the geometry (size and shape) of the board, so this result does not address Felix's question. the65thsquare claims that is hard to define "faster" or "slower", but the above definition that "faster" means "fewer moves, on average, for a decision" seems easy enough; and while I agree that a shorter checkmate is not necessarily better than a longer checkmate, it would appear to be hard to argue that the shorter checkmate is not "faster".

Felix's question (paraphrased) is this: Would regular chess be faster or slower on a Gothic Chess board (10x8)? Ed (GothicChessPro) claims that it would be faster because more games would be decided by an outside passed Pawn due to the increased width of the board. I find that hard to believe. Of course, if one could create an outside passed Pawn and exchange pieces down to a King and Pawn endgame with the opposing King outside the square of the passed Pawn, the win would indeed be simple (and fast). However, King and Pawn endgames are far from being the most common type of endgame and it is not at all clear that just because the board is wider that the proportion of games decided solely by an outside passed Pawn would be significantly higher. Here is another factor to consider: All of the elementary mates (K+Q vs K, K+R vs K, K+B+B vs K, K+B+N vs K) take longer (on average) on a 10x8 board because it takes longer to corral a King on a larger board. In fact, this is one of the points being discussed in the K+B+N vs K discussion thread. One should also take into consideration that, even though the Chancellors and Archbishops are off the board, the game may still be decided before an endgame is reached.

My personal opinion is that the "length" of a game with regular chess pieces on a 10x8 Gothic board would, on average, be very close to being the same as or only slightly longer than on an 8x8 regular board. Of course, this opinion is based on my interpretation of the theoretical considerations mentioned above, and not on any actual data, which reminds me of a well-known quote of Donald Knuth: "Be careful with the following code. I have only proved it to be correct, I haven't actually tested it." :-)