Buoyed by England's success against Australia on Monday in front of a capacity 15,000 crowd at The Rose Bowl, the ECB has already announced a crowded schedule with two Twenty20 matches against next year's touring sides - Sri Lanka and Pakistan.
Fletcher is concerned that seven home Tests will be too many for his charges in the middle of an already packed schedule.
"It's a very difficult decision to make," Fletcher said.
"But if they're going to introduce Twenty20 cricket then they have to look at reducing the numbers of Test matches so they can fit in three Twenty20 games into a five-day period. One of the forms of the game has got to suffer in order to benefit the other. We play seven Test matches in a summer so, maybe we have to play five or six or whatever it is. We can't carry on playing seven Tests, then the equivalent of seven to ten One-dayers and then another three or four Twenty20 games but it's just too much."